Infectious Diseases PDF
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This PLABABLE document provides notes, features, and treatment information for various infectious diseases, including respiratory, central nervous system, and genitourinary infections. It contains sample questions and answers on crucial topics in infectious disease pathology.
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PLABABLE VERSION 6.4 INFECTIOUS DISEASES Respiratory Infections Community acquired pneumonia Amoxicillin (mild) Community acquired Amoxicillin + pneumonia Clarithromycin (moderate) C...
PLABABLE VERSION 6.4 INFECTIOUS DISEASES Respiratory Infections Community acquired pneumonia Amoxicillin (mild) Community acquired Amoxicillin + pneumonia Clarithromycin (moderate) Co-amoxiclav + Community acquired Clarithromycin pneumonia (severe) Co-amoxiclav (amoxicillin + clavulanic acid) Pneumocystis Co-Trimoxazole Jirovecii pneumonia (trimethoprim + (prev as “P. Carinii’) sulfamethoxazole) First 2 months: RIPE Rifampicin Isoniazid Pyrazinamide Tuberculosis (TB) Ethambutol Next 4 months: RI Rifampicin and isoniazid Aspiration pneumonia Amoxicillin + (community acquired) Metronidazole PLABABLE Pneumonia Brain trainer: A 54 year old man presents to the Emergency Department with a two day history of productive cough. His temperature in hospital is 39°C. A chest x-ray was ordered revealing right lower zone consolidation. He is allergic to penicillin. What is the SINGLE most appropriate treatment for this patient? ➔ Clarithromycin or doxycycline In cases of penicillin allergy clarithromycin and doxycycline can be used as a substitute. Avoid clarithromycin if the patient is also taking a statin due to increased risk of rhabdomyolysis. PLABABLE Central Nervous System Infections Out of hospital Benzylpenicillin meningitis Cefotaxime IV or In-hospital meningitis Ceftriaxone IV Listeria meningitis Amoxicillin + Gentamicin Cryptococcal Amphotericin B meningitis Meningitis prophylaxis 1st line: Ciprofloxacin (for contacts) 2nd line: Rifampicin PLABABLE Meningitis Brain trainer: A woman over the age of 60 has meningitis in the Emergency Department. What should be administered empirically? ➔ IV ceftriaxone and IV amoxicillin Recommendations for adding amoxicillin 50 years (BNF) 60 years (Oxford Handbook of Clinical Medicine) In the exam, you will not be asked if amoxicillin should be added for a patient aged 50 to 60 since guidances differ. PLABABLE Meningitis Brain trainer: A person with headache, neck stiffness, photophobia and high fever. What is the most likely organism? If gram positive diplococci seen ➔ Streptococcus pneumoniae If gram negative diplococci seen ➔ Neisseria meningitidis If non-blanching rash seen ➔ Neisseria meningitidis PLABABLE Genitourinary Infections Infection Antibiotic Lower Trimethoprim or uncomplicated UTI Nitrofurantoin Upper UTI Cefalexin, co-amoxiclav, (Pyelonephritis) ciprofloxacin or trimethoprim Candida albicans Clotrimazole or Fluconazole (Vulvovaginal Candidiasis) Trichomonas Metronidazole vaginalis Cervicitis 1st line: Doxycycline (Chlamydia) 2nd line/pregnant: Azithromycin Cervicitis Ceftriaxone IM or (Gonorrhoea) CIprofloxacin (if sensitivity is known) Pelvic inflammatory 1st line: Ceftriaxone + diseases Metronidazole + Doxycycline Syphilis Penicillin G Genital herpes Aciclovir (HSV) PLABABLE Weakened Immunity Brain trainer: A pregnant woman has thick white marks inside her mouth. She is a smoker. What is the most likely diagnosis? ➔ Candidiasis A weakened immunity (due to pregnancy) and a more common diagnosis speaks for candidiasis. If the stem contained “cannot be rubbed off”, choose leukoplakia. PLABABLE Gastrointestinal Infection Infection Antibiotics Salmonella Ciprofloxacin OR Cefotaxime Shigella / Campylobacter Erythromycin OR Azithromycin OR Clarithromycin OR Ciprofloxacin Clostridium difficile For mild: (Pseudomembranous Oral Metronidazole colitis) For severe: Vancomycin Helicobacter pylori OAC or OAM Omeprazole Amoxicillin Clarithromycin or Metronidazole PLABABLE Clostridium difficile Brain trainer: A person with watery diarrhoea after given antibiotics for 7 days post-operatively. Three other patients have developed similar symptoms in the ward. ➔ Clostridium difficile Look at the key differences: Clostridium difficile → Severe diarrhoea + recent use of broad spectrum antibiotics + spreads easily in wards Norovirus → Severe diarrhoea + spreads easily in wards PLABABLE Clostridium difficile Vs Norovirus Here are some pro tips to help you differentiate between the two when asked in the exam Clostridium Difficile Norovirus Recent use of broad Outbreaks seen spectrum antibiotics commonly in semi-closed areas like hospital wards If both these features are in the stem, e.g. patient in a ward for a few days and given broad spectrum IV antibiotics → We would pick Clostridium Difficile Do not differentiate the two based on bloody or non-bloody diarrhoea! PLABABLE Ear, Nose & Throat infection Acute bacterial otitis Amoxicillin media Upper respiratory tract Phenoxymethylpenicillin infection: Pharyngitis Tonsillitis Laryngitis PLABABLE Laryngitis Brain trainer: A boy has a 2 day history of hoarseness of voice, dry cough, fever and malaise. On examination his vocal cords are oedematous. What is the most appropriate investigation? ➔ None required PLABABLE Skin, Joint and Other Infections Cellulitis Mastitis Flucloxacillin Diabetic Foot infection Scabies Permethrin 5% topical Septic Arthritis Flucloxacillin Vancomycin (MRSA) Osteomyelitis Toxoplasmosis Pyrimethamine + Sulfadiazine PLABABLE Oral Thrush (Oral candidiasis) Features: Thick white marks + inflamed mouth / tongue Can be rubbed out + Red inflamed painful sore mouth angles Contributing factors History of immunosuppression -diabetes, recent use of antibiotics & regular steroids eg. asthmatic Smoking Elderly Pregnancy Treatment Stop smoking Good inhaler technique and hygiene eg. use a spacer and rinse mouth after use 1st line: oral miconazole gel Oral fluconazole 50mg OD 7 days in severe cases PLABABLE Leukoplakia Features Raised edges Bright white patches Sharply well defined Cannot be rubbed out Contributing factors History of smoking Investigation Biopsy (they are premalignant for SCC) Treatment Smoking cessation Observe or surgical excision depending on biopsy result PLABABLE Streptococcus Pneumoniae Facts: The most common cause of pneumonia A gram +ve diplococci Features: Productive cough 😷 Fever Chest tightness Unilateral basal crackles on auscultation Unilateral lobar consolidation on x-ray It is associated with Herpes Labialis PLABABLE Different Types Of Pneumonia Pneumococcal Herpes Labialis streptococcal Typical features of community acquired pneumonia Also associated → Productive cough with HIV patient → Fever - CD4>200 !! → Unilateral basal crackles → Unilateral basal consolidation Lobar consolidation Mycoplasma Erythema multiforme Atypical features: → Young adult → Dry cough → Bilateral consolidation Patchy consolidation of 1 lower lobe Pneumocystis HIV with CD4 < 200 jirovecii + desaturation on exercise Dry cough Bilateral consolidation Exertional dyspnoea PLABABLE Different Types Of Pneumonia Staph. aureus Pneumonia developed after influenza (flu) Common in IV drug abuser and elderly Bilateral cavitation Legionella Pneumonia developed after exposure to water, staying in hotel Low sodium Low lymphocytes Bibasal consolidation Macrolides/Tetracyclines are usual treatment of choice Klebsiella Cavitating pneumonia Particularly upper lobe PLABABLE Type Of Pneumoniae Brain trainer: A HIV man presents with symptoms of pneumoniae. His CD4 count is measured at 350mm³. X-ray shows shows lobar consolidation. What is the most likely causative organism? ➔ Streptococcus pneumoniae PLABABLE Type Of Pneumoniae Brain trainer: A 14 year old child presents with meningitis. CSF sample collected appears purulent. If neisseria meningitidis was not amongst the options which organism would you suspect? ➔ Streptococcus pneumoniae PLABABLE Type Of Pneumoniae Brain trainer: An IV drug users presents with symptoms of pneumoniae. One week earlier he had flu like symptoms. X-ray shows bilateral cavitations. What is the most likely causative organism? ➔ Staphylococcus aureus PLABABLE Tuberculosis Facts: Caused by mycobacterium tuberculosis (Acid fast bacilli) Travelling Hx: South Asia, Sub-saharan Africa, and India Diagnosis: 1. Sputum staining for acid-fast bacilli 2. Bronchoalveolar lavage if no sputum 3. Gastric lavage if above not available (sputum might be swallow by patient during sleep) High risk factor groups: Homeless Drug abuser Smoker Low socioeconomic class PLABABLE Tuberculosis Features: Chronic productive cough Hemoptysis Weight loss (Cachexia) Fatigue Night sweats Small area of caseating granulomas Upper lobe consolidation, infiltration with cavitation on chest x-ray Cervical or supraclavicular lymph nodes may be initially tender, firm and discrete on palpation but later become suppurative PLABABLE Tuberculosis PLABABLE Tuberculosis Screening for contacts: For latent TB not acute TB Mantoux test for contact who have not been vaccinated with BCG before Interferon gamma test for contacts who have been vaccinated with BCG before Treatment 1st 2 months - RIPE Rifampicin, Next 4 months - RI Isoniazid, Rifampicin, Isoniazid Pyrazinamide, Ethambutol These are not contraindicated during pregnancy but streptomycin is!! PLABABLE Tuberculosis Directly-Observed Therapy: For patient who need support to manage TB in outpatient setting: For underserved groups Homeless Imprisoned Drug or alcohol misuse Patient who have not been adherent to therapy Patient who are too ill to adhere to therapy Toxoplasmosis can present with splenomegaly and cervical lymphadenopathy Weight loss is usually NOT SEEN. PLABABLE Tuberculous Lymphadenitis Contributing factors: Travelling history - particularly to/from India Features: Fever Cough Cervical lymphadenopathy Caseating granuloma in LNs Sarcoidosis and Crohn’s disease have NON-caseating granuloma PLABABLE Laryngeal TB Contributing factors IV drug abuser Low socioeconomic Features Fever Cough Cervical lymphadenopathy Hoarseness Dysphagia Weight loss PLABABLE Laryngeal Tuberculosis Brain trainer: A 35 year old homeless man presented with dysphagia and hoarseness for the past 4 weeks. He feels tired and has a mild fever everyday. He has also lost 18 kg in the last 4 weeks. The base of his neck has non-tender swelling bilaterally. What is the diagnosis? ➔ Laryngeal tuberculosis PLABABLE Side Effects of Anti-TB drugs Rifampicin Streptomycin RIPES Isoniazid Ethambutol Pyrazinamide ↑ uric acid ↑ risk of gout Peripheral Visual problem neuritis e.g. red-green (Give vitamin B6 discrimination as treatment) ↓ visual activity Hepatitis Optic neuritis Red-orange Ototoxic urine and Potential secretion deafness Enzyme P450 Contraindicated induction in pregnancy PLABABLE Tuberculosis Brain trainer: Which medication for the treatment of tuberculosis is contraindicated in pregnancy? ➔ Streptomycin PLABABLE Tuberculosis Brain trainer: An homeless man has tuberculosis. What is the most appropriate management of this patient? ➔ Directly observed therapy PLABABLE Scabies Facts: Organism is Sarcoptes scabiei → A parasite causes skin infestation Transmitted by skin to skin contact Causes allergic reaction → Pruritus NOT infection Features: Linear tracks on skin (Burrows) Severe pruritus (particularly night time) Particularly in area of skin folds, flexures of: ○ Wrists ○ Finger webs ○ Elbow ○ Axilla ○ Areola ○ Genitalia Treatment: Permethrin 5% cream Simultaneously treat all close contacts Hint: Nursing home!! PLABABLE Scabies Keywords Keywords to remember for scabies to answer majority of scabies questions Common in nursing homes Sarcoptes Very itchy Linear tracks on skin Allergic reaction that causes itch Permethrin PLABABLE Scabies Brain trainer: What is the mechanism of itching in a scabies infection? ➔ Allergic reaction PLABABLE Gastroenteritis Features: Nausea Vomiting Diarrhea ± blood Abdominal pain Investigations: Stool microscopy, culture and sensitivity FBC, renal function and electrolytes Treatment: Usually conservative If severe, bloody diarrhoea ➔ Campylobacter jejuni - Clarithromycin ➔ Salmonella- Ciprofloxacin In UK, patients are allowed to return to work 48 hours after the last episode of symptoms (Diarrhoea or vomiting) PLABABLE Meningitis Otitis media Meningitis Hearing loss Delayed complication MUST arrange a hearing test No later than 4 weeks after treatment PLABABLE Kaposi Sarcoma Cancer of connective tissue most commonly caused by HIV/AIDS Blood vessels ↑ in size Features: Red, purple, brown or black nodules or papules Usually non-painful Mouth, nose or throat are common sites Can grow internally (eg. lungs, GI tract) PLABABLE Kaposi Sarcoma Risk factors Homosexual Mediterranean Jewish AIDS patient Bisexual PLABABLE Chicken Pox Caused by varicella zoster virus Infectious route: Very contagious Mainly via respiratory route - airborne Can be transmitted by direct contact with vesicles Dried out and crusted vesicles CANNOT transmit Infectious period: 2 days BEFORE rash 5 days AFTER rash first appeared Stop when vesicles dried out and crusted Features: Fever (38-39 ℃) Pruritic rash (itchy) Rash: 1. Macules 2. Papules 3. Vesicles 4. Dry crust Usually starts on face or trunk and then may spread over entire body PLABABLE Chicken Pox - Management < 12 years old Reassurance + Oral antibiotic if supportive superimposed measures. infection is suspected: Paracetamol for Fever fever Discharging Antihistamines pustules and calamine Redness around lotion for itching vesicle Pinkish fluid secretion When can children go After vesicles back to school after dried out and chicken pox? crusted Usually 5 days after onset PLABABLE Chicken Pox - Management For Pt with exposure: Pregnant (20 weeks Varicella-zoster and less) with no VZ Immunoglobulin antibodies (VZIG) Newborn with peripartum exposure from mother (+/- 7 days of birth) For Pt who develops chicken pox: Aciclovir Immunocompromised Pregnancy For Pt with exposure: These changes are new from the Pregnancy over 20+1 guidelines from weeks Public Health Immunocompromised England (2019) On chemotherapy, on long term steroid = Immunocompromised PLABABLE Chicken Pox - Management Another way to remember the management for those who have been in contact but no rash Susceptible individuals (ie. contacts - this person has been in contact with a person with chickenpox) are divided into three: 1 Immunosuppressed Oral antivirals first line If contraindicated (renal impairment of intestinal malabsp), then VZIG 2 Neonates VZIG 3 Pregnant women Up to 20+0 weeks = VZIG Over 20+1 weeks = Oral antivirals (preferred over VZIG) → VZIG can still be used if antivirals not an option in the exam This is an interim update → The reasons for the interim update is because of the national VZIG shortage PLABABLE Chicken Pox Brain trainer: An adult has chicken pox with a fever of 39.1 and pinkish white thick fluid is seen secreted from a few of the lesions. What is the most appropriate medication to prescribe? ➔ Oral antibiotics PLABABLE Chicken Pox Brain trainer: An immunocompromised man reports that his partner currently has chicken pox. His history is positive for chicken pox in childhood. What is the most appropriate action? ➔ Obtain serology for varicella immunity PLABABLE Chicken Pox Brain trainer: A 7 year old boy develops a fever and crops of vesicles on his head, neck and trunk. What is the main mode of transmission? ➔ Airborne Varicella zoster is mainly transmitted via respiratory droplets as opposed to contact PLABABLE Chicken Pox Brain trainer: A 72 year old man is exposed to chickenpox. He has been taking high dose of oral prednisolone over the past 3 months as part of his management for polymyalgia rheumatica. He has not had any chickenpox before previously. What is the most appropriate management? ➔ Oral acyclovir It is improper to stop or reduce his steroid dose. PLABABLE Chicken Pox Knowing the infectious period and incubation period of chickenpox is important. Example If an asymptomatic woman who is 18 week gestation is in significant contact with a child 8 days ago who later developed chicken pox, ask yourself when did he develop the chicken pox rash? If he developed it a day ago then at that time he saw her, he was not infectious → Action: Reassure (infectious period 2 days before the rash starts) If he developed it a day after he has seen her, then he would be infectious at that time → Action: Give woman intravenous IVIG if she is tested negative for VZV antibodies (incubation can be as long as 21 days so even if she has not developed the rash, she still can) Infectious period: 2 days BEFORE rash 5 days AFTER rash first appeared Stop when vesicles dried out and crusted Incubation period: As long as 21 days PLABABLE Chicken Pox RECAP - Numbers to remember in Chickenpox 2, 5, 21, 7 Infectious period: 2 days BEFORE rash 5 days AFTER rash first appeared Stop when vesicles dried out and crusted Incubation period: As long as 21 days Newborn administration of IVIG Newborn with peripartum exposure from mother (+/- 7 days of birth) → Administer IVIG to newborn PLABABLE Shingles Facts: It is caused by varicella zoster virus (VZV) It is a reactivation of VZV especially in immunocompromised / old patients Presented as chicken pox at initial VZV infection Virus remain inactive in nerve cells Features: Painful skin rash with blisters in localized area Management: Obtain serology for varicella immunity in immunocompromised patients Immunocompromised- HIV positive, diabetic, on long term steroids Treatment: Aciclovir Pain management PLABABLE Ramsay Hunt Syndrome (Herpes zoster oticus) Facts: It is a reactivation of VZV Localised in geniculate ganglion of the facial nerve (7th CN) Features: Facial palsy (ipsilateral facial palsy, loss of taste) Otalgia - ear pain Tinnitus Vertigo Unilateral hearing loss Painful rash or vesicles around ears or on auditory canal Treatment: Oral aciclovir Oral corticosteroid Amitriptyline for pain PLABABLE Ramsay Hunt Syndrome (Herpes zoster oticus) PLABABLE PLABABLE Herpes Zoster Ophthalmicus Facts: It is a reactivation of VZV Localised in ophthalmic branch of trigeminal nerve (5th CN) Features: Conjuntivitis Keratitis Painful rash or vesicles around eyes Treatment: Oral aciclovir Oral corticosteroids Same day ophthalmology review Even immunocompromised patients can still take oral aciclovir There is still a role for intravenous aciclovir but it is usually reserved for: Severely immunocompromised with a widespread rash Systemically unwell Issue with absorption of oral aciclovir (e.g. inflammatory bowel disease) PLABABLE Herpes Zoster Ophthalmicus Hutchinson’s sign Vesicles on the tip of the nose increases the risk of eye involvement PLABABLE Herpes Zoster Ophthalmicus Patient with: Hutchinson’s History of sign Crohn’s disease Best not to use oral aciclovir but to use IV aciclovir PLABABLE Herpes Zoster Ophthalmicus Brain trainer: A patient has suspected shingles with a rash present on the tip of the nose. What is this finding called? and what is its significance? ➔ Hutchinson's sign → ocular involvement PLABABLE Lyme disease (Lyme borreliosis) History of camping or walking in jungles or gardens >>>Ticks bite Beginning stage: Erythema migrans (erythematous, painless, non-itchy) + fever, headache, myalgia and general aches) It could present as an annular rash with scaly edge, slow growing with general aches and pain Later stage: Facial paralysis Meningitis AV heart block Myocarditis Arthritis PLABABLE Lyme Disease (Lyme borreliosis) Diagnosis: Check for antibodies to Borrelia- Burgdorferi Treatment: Doxycycline or amoxicillin if contraindicated e.g. pregnancy Ceftriaxone in disseminated disease PLABABLE Lyme Disease Brain trainer: A pregnant woman has lyme disease in the early stages. What is the most appropriate management? ➔ Amoxicillin PLABABLE Meningitis In Babies And Toddlers Fever, Refusing cold food and hands vomiting and feet Rapid Fretful, breathing dislike and being grunting handled Stiff neck, Unusual dislike crying, bright moaning lights Tense, Pale, bulging blotchy fontanelle skin, (soft spot) spot/rash Drowsy, Convulsion floppy, or seizures unresponsive PLABABLE Meningitis In Babies And Toddlers Behaviour Irritable: unusual crying/moaning changes Refusing food Drowsy, floppy, unresponsive Neurologic Tense bulging fontanelle findings Stiff neck Photophobia Associated Fever findings Vomiting Rapid breathing/grunting Rash (suspect meningococcal) Complications Seizures PLABABLE Meningitis Hx of Fever seizures Vomiting Altered mentation Photophobia Headache Diagnostic investigation Without rash With rash Lumbar puncture = CSF analysis Blood culture Contraindications: Check for ↑Intracranial Pressure Meningococcal Bulging, tense septicemia fontanelle Ongoing seizures → Neisseria GCS < 9 or meningitidis a drop of > 3 Unequal, dilated, unresponsive pupils Papilledema PLABABLE Meningitis Treatment for meningitis ASAP Health protection team must be notified immediately once there is a clinical suspicion of meningitis!!! In exam, look out for the points below: Arthralgia and muscle aches Cold periphery Photophobia Pale or mottled Severe skin headache SOB Neck stiffness Rash Septicemia Meningitis PLABABLE Meningitis Treatment Suspected meningitis Presented to Presented to GP setting hospital setting IM or IV IV ceftriaxone benzylpenicillin or cefotaxime Allergic to penicillin or cephalosporins? Chloramphenicol PLABABLE Meningitis Treatment Amoxicillin or Listeria meningitis Ampicillin + Gentamicin Cryptococcal Amphotericin B meningitis 1st: Ciprofloxacin Meningitis contact or prophylaxis Rifampicin IV Ceftriaxone + Elderly >60 IV Amoxicillin PLABABLE Schistosoma Features: Hx of travelling to Africa (mostly) Pruritic skin rash at site of penetration Fever, maculopapular rash, headache, weight loss + Hepatomegaly Haematuria (dark and red urine) Schistosoma organisms Schistosoma Schistosoma ManSoni HaematobiUm Affects inteStine Affects Urinary and liver bladder Haematuria, UB Hepatomegaly calcification and obstructive uropathy These features are caused by 2 different species PLABABLE Schistosoma Haematobium Features: Hx of travel to Africa (mostly) Haematuria Urinary bladder calcification Ulceration and obstructive uropathy Increased bladder cancer risk Investigations: X-ray: ○ Urinary bladder calcification Ultrasounds: ○ Hydronephrosis ○ Thickened bladder wall CT scan ○ Urinary bladder calcification ○ Obstructive uropathy Important notes: Can lead to bladder cancer May be after up to 20 years post-infection Similar organisms: Schistosoma mansoni ○ Affects intestines, liver and spleen ○ Hepatomegaly PLABABLE Schistosoma Haematobium SChistosoma HAEMAtobium SCc (squamous cell HAEMAturia as part of carcinoma) of bladder the clinical features as a complication years later PLABABLE Malaria Features: Hx of travel to Africa Intermittent fevers Rigours Headache Malaise Cough Myalgia Gastrointestinal upset Hepatosplenomegaly Jaundice Investigations: Microscopy of thick and thin blood film (most accurate) Full blood count may show anaemia and thrombocytopenia Rapid diagnostic test → Used as adjunct to blood films and not a replacement Important note: Avoid the belief that prophylaxis prevents all malaria PLABABLE Cerebral Malaria Features: Hx of travelling to Africa Meningitis-like symptoms: ○ Fever and chills ○ Neck stiffness ○ Vomiting ○ Impaired consciousness Anaemia → Differentiate from meningitis To suspect! Hx of travel to malaria affected area(s) In the past year particularly over the last 3 months Malaria prophylaxis does not guarantee full protection against all subtypes of malaria PLABABLE Treatment For Malaria Our honest opinion is that Malaria treatment is so low yield in the exam that you would be able to get away without remembering Malaria treatment at all. If at all, perhaps just remember this: Chloroquine is the drug of choice for non-falciparum malaria Primaquine is used to destroy liver stage parasites an prevent relapse The next card (Treatment for Malaria) is only applicable if you really want to know it in depth but again, it is LOW YIELD (unlikely to be asked). PLABABLE Treatment For Malaria 1. Primaquine If blood film shows ring form Plasmodium with schuffner’s dots To be used at latent/dormant stage of Plasmodium ovale or vivax latent hypnozoites in liver Targets and eradicate all stages - liver latent and RBCs Contraindicated for patients with G6PD as it can cause severe haemolysis Contraindicated for pregnant and breastfeeding patients *MUST screen for G6PD deficiency before commencing on therapy* 2. Chloroquine In non-falciparum / non-hypnozoite malaria To be used in active stage and targets RBCs Can be used in pregnancy Not effective in chloroquine-resistant area(s) e.g. Sub-Saharan Africa 3. Quinine To be used when chloroquine fails 4. Mefloquine To be used if travelling to chloroquine-resistant area(s) Can be used in pregnancy PLABABLE Treatment For Malaria Brain trainer: An African woman has malaria. Blood film shows ring form plasmodium with schuffner's dots in red blood cells. What is the SINGLE most appropriate drug to eradicate this infection? ➔ Primaquine PLABABLE Malaria Vs Meningitis The following points would lean you towards a suspected diagnosis Malaria Meningitis Fever, malaise, headache Travel history to malaria affected area(s) Living in crowded areas Photophobia Jaundice Rash Splenomegaly, hepatomegaly Thick and thin blood film Lumbar puncture for microscopy Malaria prophylaxis does not guarantee full protection against all subtypes of malaria Malaria rarely presents with signs of meningism PLABABLE Needle Stick Injuries Being pricked by a needle Basic 1st aid Washing with soap under running water Encouraging bleeding in affected area Request patient’s permission to investigate any blood-borne infection (HIV, HCV and HBV) Low risk: Safe sexual High risk: intercourse e.g. IV drug abuser, Does not use IV drug addicts drugs Test healthcare Start professional for post-exposure hepatitis B surface prophylaxis (PEP) antibody Offer hepatitis B booster If booster was not received previously If healthcare professional cannot remember when last dose was PLABABLE Needle Stick Injuries Risk of transmission from needle stick injuries Hepatitis B HIV Hepatitis C 30% 0.3% 3% Healthcare professionals should return in 6 weeks and check for HIV and HCV Patient should always be tested for HIV, HCV and HBV Healthcare professional should always be tested for hepatitis B surface antibody and offer hepatitis B booster if cannot remember when was last dose in low risk injuries PEP should be offered to healthcare professionals if injuries is high risk PLABABLE Surgical Prick Injury Brain trainer: A surgeon is pricked by a needle used during an appendectomy. What action should be taken? ➔ Patient: test HBV, HCV, HIV ➔ Surgeon: store blood, test HBV, offer HBV booster PLABABLE HIV Post-Exposure Prophylaxis (PEP) Antiretroviral medications to be given as soon as possible after exposure: Non-safe sexual intercourse with high risk individual Needle stick injury when from: ○ High risk source ○ High risk bite e.g drug addict To be started ASAP 1-2 hours, up to 72 hours after exposure To complete a 28 days course of PEP If human bite: co-amoxiclav 7 days or metronidazole + doxycycline if penicillin allergic Recheck HIV viral load after 6 months Aim: viral load < 200 PLABABLE Bite Injury Brain trainer: A police officer is bitten by a drug user. What would you offer the police officer? ➔ Post-exposure prophylaxis PLABABLE Vaccine To Avoid In HIV Patients If patient is HIV positive BCG If CD4 count vaccine low Yellow MMR fever vaccine vaccine PLABABLE Vaccine To Avoid In HIV Patients Brain trainer: How is the vaccination schedule for a HIV positive infant? ➔ All vaccines as scheduled except BCG vaccine PLABABLE Tetanus Vaccination Vs Tetanus Immunoglobulins Vaccination Immunoglobulins Contains deactivated exotoxins (toxoids) Ready made antibodies against the tetanus toxin Administered if tetanus toxin is already present in the body or Immune response the patient is resulting in suspected of getting it antibodies (in certain situations) Takes time to take Takes effect almost effect (upto a month) immediately PLABABLE Tetanus Prophylaxis (after injury) 1. Is wound high risk - dirty, contaminated or compound fracture? Yes No Give IM human tetanus No need for IM immunoglobulins human tetanus If booster given 10+ immunoglobulins yrs ago or uncertain immune status 2. Person’s immunization status? Fully immunised and up-to-date Unknown or i.e. completed 5 incomplete doses of tetanus vaccine + last dose Give complete within 10 years course of tetanus vaccine No need for tetanus (5 doses) vaccine Or full course of diphtheria, Sometimes we give tetanus and Abx for wound with pertussis high risk of infection vaccine PLABABLE Tetanus Prophylaxis Terms to remember Priming course → First 3 doses of vaccine Tetanus-prone wound examples: Puncture type injuries in garden Burns Bites from animals in agricultural environment High-risk tetanus prone wound examples: Tetanus prone wounds containing one of the following: Soil Wounds/burns displaying extensive devitalised tissue Wounds/burns requiring surgical intervention that has been delayed for more than 6 hours PLABABLE Tetanus Prophylaxis ADULTS Immunisation WOUND type status Clean Tetanus- High-risk prone tetanus prone Completed Reassure Reassure Reassure priming course + Booster in past 10 years Completed Reassure Tetanus Tetanus priming course vaccine vaccine + and tetanus NOT had Ig booster in past 10 years Unsure of Tetanus Tetanus Tetanus vaccination vaccine vaccine vaccine status and and tetanus tetanus Ig Ig PLABABLE Tetanus Prophylaxis CHILDREN Immunisation WOUND type status Clean Tetanus- High-risk prone tetanus prone Up to date Reassure Reassure Reassure with vaccination schedule Completed Reassure Tetanus Tetanus priming course + Booster vaccine vaccine + to bring and tetanus Overdue next them up to Ig routine tetanus date with immunisation vaccine schedule Not completed Tetanus Tetanus Tetanus priming course vaccine vaccine vaccine or unsure of and and tetanus vaccination tetanus Ig Ig status PLABABLE How To Give Tetanus Vaccine Adult who has not been immunised 5 doses required First 3 doses should be given 1 month apart Remaining 2 are boosters 1st booster give at 5 years after primary course 2nd booster give at 10 years after first booster Children (below 10) who has not been immunised 5 doses required First 3 doses should be given 1 month apart Remaining 2 are boosters 1st booster give at 3 years after primary course 2nd booster give at 10 years after first booster Can be given as diphtheria, tetanus, pertussis combined vaccine Remember: 1. Dirty wound? → Immunoglobulines 2. Immunisation status? → Vaccine 3. High risk infection? → Antibiotics PLABABLE Tetanus Prophylaxis Brain trainer: A man presents with a deep penetrating wound after stepping on a nail which was heavily contaminated with soil. He has completed a full priming course of tetanus vaccine with the last dose within 10 years. What is the most appropriate management to be given? ➔ Reassure PLABABLE Tetanus Prophylaxis Brain trainer: A man presents with a penetrating wound after cutting his arm on the fence at the garden. He has completed a full priming course of tetanus vaccine. His last vaccine was more than 10 years ago. What is the most appropriate management to be given? ➔ Tetanus booster vaccine PLABABLE Tetanus Prophylaxis Brain trainer: A 3 year old child has sustained a clean wound injury. She has not had any immunisations before. There are no contraindications to immunisation for her. What is the most appropriate management? ➔ Administer DTP vaccination immediately and arrange follow up with GP to complete DTP vaccination course PLABABLE Tetanus Prophylaxis One word of advice Remember what options NOT to pick in the exam Any option that says “Tetanus immunoglobulins alone” can be crossed out. Why? This is because in any case where you give tetanus immunoglobulins, you would also give a tetanus vaccination. X Tetanus immunoglobulins alone PLABABLE Mumps - Paramyxovirus Facts: Contagious and infectious virus Transmitted via close contact e.g. droplet of saliva Features: Bilateral parotitis: pain and tender swelling at angles of jaw - periauricular Swelling of parotid salivary gland Fever Dry mouth - due to blockage of salivary gland DIfficulty in opening mouth or talk - due to swelling Orchitis (4-5 days post parotitis) - NOT always ○ Severe testicular pain ○ Swollen edematous scrotum ○ Impalpable testes ○ Risk of sterility in males Treatment: Symptomatic relief only - paracetamol or ibuprofen Reassurance PLABABLE Hepatitis A Transmission → Faecal oral route Presentation Pruritus Jaundice Prodromal symptoms like myalgia athralgia Investigations ALT much higher than AST Anti HAV IgM antibody → Detected around the time symptoms develop Anti HAV IgG antibody → Detectable soon after IgM and remains detectable for life Tip If suspect acute hepatitis A infection → Request IgM antibody PLABABLE Hepatitis B Serology HB Ag S E Anti C Hepatitis B Antigen Surface Envelope Antibodies Core In acute and 1st marker HBs that become chronic Ag abnormal after infection +ve acquiring hepatitis B +ve HBs infection Ag Highly infectious - active viral replication HB eAg to spread +ve eAg Antibodies against eAg Anti- Develops of eAg indicates +ve HBe response to treatment Post vaccination against Anti- HBV HBs Recovery and immunity +ve against HBV +ve Anti- Anti- HBe HBc At onset of symptoms Due to reaction to Remain +ve after core antibody treatment against HBV PLABABLE Hepatitis B Serology +ve First marker to become HB abnormal in both acute and sAg chronic infection +ve HB Indicates highly infectivity eAg +ve Anti- Indicates recent vaccination HBs +ve Anti- Indicates past infection and HBc remain positive after recovery +ve IgM Indicates recent acute Anti- infection HBc +ve HBV Shows infectivity (Acute viral DNA replication) PLABABLE Hepatitis B Serology Anti- HBc -ve HB Susceptible sAg Anti- -ve HBs -ve +ve -ve Anti- HBs Immune due to HB natural sAg infection Anti- +ve HBc -ve HB +ve Immune due to sAg Anti- Hep B HBs vaccination Anti- HBc -ve PLABABLE Hepatitis B Serology +ve +ve HB IgM sAg Anti- HBc Acute infection Anti- Anti- HBs -ve +ve HBc +ve -ve IgM HB Anti- sAg HBc Chronic +ve -ve infection Anti- Anti- HBc HBs Press the icon for one of our teaching videos by Dr Asim Ahmad PLABABLE Hepatitis C Workup IV drug user + abnormal LFTs (high bilirubin, high ALT, high AST, ALT>AST) Suspect viral hepatitis Suspecting hepatitis C? Remember to perform a hepatitis C antibody test first! HCV RNA test (PCR) is performed later on if antibody tests come out to be positive PLABABLE Hepatitis C Presence of Current Hepatitis C HCV infection RNA PLABABLE Hepatitis B Serology Brain trainer: What blood result confers successful vaccination for hepatitis B? ➔ Positive: anti-HBs ➔ Negative: HBsAg, anti-HBc PLABABLE Genital Ulcers Genital Haemophilus Syphilis herpes ducreyi (HSV) Multiple painful ulcers Single Single Painful non-painful Or Multiple ulcer ulcers + Dysuria Rx: Aciclovir Investigation: Viral culture + NAAT or DNA detection using PCR (Polymerase chain reaction) IF negative and ulcer are recurrent → Check for anti-HSV antibody PLABABLE Painful Genital Ulcer(s) Painful ulcer(s) on Genitalia → Herpes simplex virus or Haemophilus ducreyi? Herpes simplex Haemophilus virus (genital ducreyi herpes) (chancroid) Starts off as multiple Starts off as an painful vesicles erythematous papular lesion Progresses to a Progresses to single or multiple multiple painful painful ulcers ulcers (Usually single and deep) Associated with May have history malaise, fever, from coming from a myalgia developing country PLABABLE Type of Test Brain trainer: A man presents with a painful deep ulcer on the penis. It is associated with painful inguinal lymphadenopathy. He is sexually active. What investigations is indicated? ➔ Swab for haemophilus ducreyi PLABABLE Painful Genital Ulcer(s) Painful ulcer(s) on Genitalia → Herpes simplex virus or Haemophilus ducreyi? In terms of investigation, does it matter? No Both can be diagnosed if required by a PCR swab of the base of the ulcer If PCR, not present in the options, then choose a viral culture. PLABABLE Type of Test Brain trainer: What diagnostic tests are utilised for diagnosing a primary herpes simplex virus infection? 1. PCR-based method 2. Viral culture PLABABLE Leptospirosis Leptospirosis Ask yourself, what do you see in this picture that reminds you of weil’s disease? Spirochete Rat Well (Weil’s) disease PLABABLE Campylobacter Jejuni Facts: It is gram -ve on stool culture and sensitivity It is a gram -ve curved bacilli ‘rods’ Features: Hx of travel Prodrome (initially): High fever 40℃ Watery diarrhoea at start Headache Myalgia Bloody diarrhoea after Treatment: It is mostly self-limiting with good hydration Abx in severe cases: ○ Erythromycin or clarithromycin or azithromycin ○ 2nd line - ciprofloxacin Notes on other suspected infections: Cholera is gram -ve comma-shapes Streptococcus pneumoniae is gram +ve diplococci Staphylococcus aureus is gram +ve and coagulase +ve cocci ‘round’ PLABABLE Travellers’ Diarrhoea Salmonella Shigella Campylobacter All are gram -ve bacilli ‘rod’ It is self-limiting, not treatment required BUT for elderly or immunocompromised Treatment for campylobacter: Treatment for 1st line: salmonella: Erythromycin Clarithromycin Ciprofloxacin Azithromycin 2nd line: Ciprofloxacin PLABABLE Leptospirosis Facts: It is spread by contact with urine of infected animals (direct transmission) Or water that has been contaminated by urine of infected animals (indirect method) Features: Hx of travel and water exposure + Animal contact Presented initially with red eyes (subconjunctival haemorrhage) Then yellow eyes (jaundice) Fever, rigors, malaise, arthralgia, myalgia Investigations: Serology (mainstay) ○ Ab detectable 10d after infection PCR allows early detection Culture can take months Treatment: Self-limiting Oral doxycycline for mild cases Ampicillin or benzylpenicillin for severe cases PLABABLE Brucellosis Facts: It is most commonly spread by inhalation from infected livestock in endemic areas Or skin contact by veterinarians or abattoir workers Features: Hx of travel to endemic area (e.g. South America) Animal or raw meat contact Presents initially with flu-like symptoms Lymphadenopathy, splenomegaly, hepatomegaly Arthritis Investigations: Presumptive diagnosis by serum agglutination or rose Bengal test Direct isolation of Brucella spp (Gold standard) Treatment: Simple infection - doxycycline PLABABLE Brucellosis Think South America Farms Infected animals Remember, if the patient is traveling Unpasteurized milk from Central America, the answer CANNOT be Febrile disease, Brucellosis because it enlarged spleen, is virtually eliminated sweating, arthralgia in developed countries PLABABLE Cerebral toxoplasmosis Facts: Caused by Toxoplasma gondii Lives and reproduces in Cat’s guts Reactivated in patients with HIV infection when CD4 is low ( 38.5℃ or 2 consecutive temperature > 38℃ Neutrophil count < 0.5 x 109/L Treatment: Start empirical antibiotic IMMEDIATELY IV tazocin (tazobactam + piperacillin) If patient still present with feature(s) above after 48 hours: → Meropenem + vancomycin If patient remain unwell after 4-6 days: → Investigate for fungal infection → Continue antibiotics → Add IV antifungal Start IV Abx in all patients who are unwell with fever and have recent chemotherapy, regardless of neutrophil count PLABABLE Necrotising Fasciitis Facts: Mainly caused by group A beta-hemolytic streptococci An infection spread deep and involves deep layers (dermis, subcutaneous tissues, fascia and muscles) Life threatening and rapidly spread into deep layers IM and SC injections, immunosuppression and diabetic are risk factors Features: Presented as cellulitis initially (first 1-2 days) ○ Erythema ○ Swelling ○ Pain over the affected area(s) Then it will be presented as bullae ○ Grey/black skin (necrosis) ○ Hard subcutaneous tissue Eventually septic shock Severe Pain Treatment: Urgent surgical debridement IV antibiotics - clindamycin or benzylpenicillin *This condition DOES NOT respond to flucloxacillin* Differ from erysipelas as necrotising fasciitis is diffuse and deep. Erysipelas is well demarcated infection PLABABLE Prophylaxis Antibiotics For HIV Positive Patients HIV positive patients If CD4 If CD4 < 200 < 50 Co-trimoxazole Azithromycin Against Against pneumocystis jirovecii mycobacterium avium PLABABLE Abscess Features: High fever Erythematous skin swelling Neck abscess if large enough can cause dysphagia Treatment: IV antibiotics Incision Drainage Key point to THINK SEPSIS Unresponsive or response to only voice/pain Acute confusion state Systolic blood pressure < 90 mmHg Heart rate > 130/min Respiratory rate > 25/min Require oxygen support to keep SaO2 > 92% Non-blanching rash Mottled, ashen, cyanotic Not passed urine over last 18 hrs or urinary output < 0.5 mL/kg/hr Lactate > 2 mmol/L IV antibiotic ASAP if sepsis, NOT oral PLABABLE Whipple’s Disease Facts: It is a rare multisystem disorder Caused by tropheryma whippelii infection Features: Malabsorption - weight loss and diarrhoea Large joint arthralgia Lymphadenopathy Skin hyperpigmentation and photosensitivity Pleurisy Pericarditis Neurological symptoms (rare): ○ Ophthalmoplegia ○ Dementia ○ Seizure ○ Ataxia ○ Myoclonus Investigations: Jejunal biopsy shows: ○ Stunted Villi ○ Deposition of macrophages containing Periodic acid-Schiff (PAS) granules Treatment: Co-trimoxazole for a year + preceded by course of IV penicillin PLABABLE Important Investigation Result For Diagnosis Whipple’s Disease: Jejunal biopsy shows: ○ Deposition of macrophages containing periodic acid-Schiff (PAS) granules Celiac Disease: Jejunal/duodenal biopsy shows: ○ Villous atrophy ‘shortening’ ○ Crypt hyperplasia ○ Lymphocytosis Lymphoma: Patient with known celiac disease Duodenal biopsy shows: ○ Lymphomatous infiltrates T-cell lymphoma is a rare complication of celiac disease PLABABLE Mastitis / Breast Abscess Commonly caused by Staph. Aureus Via breast feeding Notes on breastfeeding If mother has: HIV AVOID breastfeeding Breast Continue abscess breastfeeding Nipple Continue Candidiasis breastfeeding Continue breastfeeding Hepatitis B (if baby has received Hep B vaccine) Continue breastfeeding Hepatitis C (unless nipples is cracked or bleeding) Continue breastfeeding Tuberculosis (Baby needs BCG vaccinated ASAP) Continue breastfeeding Depression (if mother is on Sertraline) PLABABLE Rabies Brain trainer: What is the only circumstance in which rabies vaccination is indicated in the United Kingdom? ➔ Bat bite Neither domestic nor wild animals (aside from bats) are carriers of the rabies virus in the UK PLABABLE Staphylococcus Aureus Staphylococcus aureus is a Gram-positive, round-shaped bacterium Which conditions do you pick it as the most likely aetiology? Breast abscess Osteomyelitis Elderly patient with bilateral cavitation with a recent history of influenza PLABABLE Cellulitis Treatment First line (uncomplicated) Flucloxacillin Penicillin allergy Doxycycline Erythromycin Clarithromycin Other options Clindamycin can be used as an alternative to fluclox (usually in severe infections) Ways to remember This depends on how much brain space you have Small brain space More brain space (Basic level) (Advance level) Just remember: Use mnemonic DECC Flucloxacillin Fluclox First → First line DEC → Doxy, Clarithromycin erythro, clarithro for → Penicillin allergy penicillin allergy Clindamycin → Alternative for severe infections PLABABLE Image Attributions https://pixabay.com/vectors/bacteria-virus-illness-bacterium-156869/ OpenClipart-Vectors Pixabay license - free for commercial use https://pixabay.com/vectors/coronavirus-emoji-mouth-guard-5107832/ iXimus Pixabay license - free for commercial use https://pixabay.com/vectors/bugs-beetles-ticks-insect-insects-575504/ OpenClipart-Vector Pixabay license - free for commercial use https://commons.wikimedia.org/wiki/File:Human_tongue_infected_with_oral_candidiasis.j pg James Heilman MD CC-BY SA 3.0 https://commons.wikimedia.org/wiki/File:CandidiasisFromCDCinJPEG03-18-06.JPG Sol Silverman, Jr., D.D.S. Public domain https://commons.wikimedia.org/wiki/File:Orale_Leukoplakie.jpg Klaus D. Peter, Gummersbach, Germany CC-BY 3.0 https://commons.wikimedia.org/wiki/File:Leukoplakiaaitor.jpg Aitor III Public domain https://commons.wikimedia.org/wiki/File:Pulmonary_tuberculosis_symptoms.png Mikael Häggström Public domain https://commons.wikimedia.org/wiki/File:Scabies-RechterFuss.jpg Penarc CC-BY 3.0 https://en.wikipedia.org/wiki/File:Kaposi%27s_Sarcoma.jpg National Cancer Institute, AV-8500-3620 Public domain https://commons.wikimedia.org/wiki/File:Kaposis_sarcoma_01.jpg M. Sand, D. Sand, C. Thrandorf, V. Paech, P. Altmeyer, F. G. Bechara CC-BY 2.0 https://commons.wikimedia.org/wiki/File:Chickenpox_Adult_back.jpg F malan CC-BY SA 3.0 https://nl.m.wikipedia.org/wiki/Bestand:Herpes_zoster_neck.png Gentgeen assumed CC-BY SA 3.0 https://commons.wikimedia.org/wiki/File:Shingles_on_the_chest.jpg Preston Hunt CC-BY 3.0 https://commons.wikimedia.org/wiki/File:Erythema_migrans_-_erythematous_rash_in_Ly me_disease_-_PHIL_9875.jpg James Gathany Publid domain PLABABLE Image Attribution https://commons.wikimedia.org/wiki/File:Adult_deer_tick.jpg Photo by Scott Bauer. Public domain https://pixabay.com/vectors/baby-boy-girl-neutral-child-cute-507133/ Glamazon Pixabay license - free for commercial use https://www.publicdomainpictures.net/en/view-image.php?image=240924&picture=happy -cartoon-family Rheo Gauthier Public domain https://en.wikipedia.org/wiki/File:World_map_green.png Derivative work: Gaaarg CC-BY SA 3.0 PLABABLE