Immunity & Oseltamivir

Immunity

• Adaptive immunity is specific, has memory, and is more effective, though slower to act.
• Active immunity involves humoral (B cells and antibodies/immunoglobulins) and cell-mediated (T cells) responses.
• Immunoglobulins recognize, bind to, and help destroy antigens like bacteria and viruses.
• Passive immunity involves the transmission of preformed immunoglobulins, such as antibodies passed from mother to fetus or plasma transplants from a donor to a patient.

Antivirals: Oseltamivir

• Antivirals generally block entry into cells or are active inside host cells.
• Oseltamivir is a neuraminidase inhibitor active against Influenza A and B.
• It prevents the release of the virus, halting the spread of infection.

Oseltamivir: Monitoring

• Renal function should be monitored in older and debilitated patients.
• Older patients should be assessed for confusion, hallucinations, and cognitive impairment.
• Start within 48 hours of symptom onset for both prophylaxis and treatment of Flu A and B.

Antiretroviral Therapy (ART) for HIV

• ART is used exclusively for HIV, particularly HIV-1 in humans and HIV-2 in animals.
• Combines three or more medications from two different classes to reduce the viral load in the blood; initiate within 14 days of diagnosis.
• ART regimen is determined by comorbid conditions, convenience, gender, pretreatment CD4 T cell count, genotypic drug resistance testing, HLA B*5701 testing (if considering abacavir), patient adherence potential, potential adverse drug effects, potential drug interactions, and pregnancy potential.

Challenges with Antiretroviral Therapy

• Healthcare providers face challenges such as substance abuse, domestic violence, lack of childcare, and unstable living conditions.
• Complex medication issues include lack of health insurance, opportunistic infections, mental illness, and chronic pain.
• Financial assistance may be available through state AIDS programs or pharmaceutical co-pay assistance.
• Resistance can develop due to poor adherence, drug-food interactions, and abnormal pharmacokinetics.
• Discontinuation or interruption due to illness, toxicity, surgery, or medication unavailability can lead to viral load rebound, immune decompensation, and clinical progression.

Goals of Antiretroviral Therapy

• Achieve maximal suppression of plasma viral load for as long as possible.
• Delay medication resistance.
• Preserve CD4 T-cell numbers.
• Confer substantial clinical benefits, reducing morbidity and mortality.

Factors Increasing Antimicrobial Resistance

• Recent antibiotic use.
• Overuse of broad-spectrum antibiotics.
• Age less than 2 years or greater than 65 years.
• Daycare attendance or exposure to young children.
• Multiple medical comorbidities.
• Immunosuppression.

Antibiotic Cross-Sensitivity and Resistance

• Beta-Lactams and PCNs, and Beta-Lactams and Cephalosporins can exhibit cross-sensitivity and cross-resistance.
• Both drug classes contain a beta-lactam ring, making them vulnerable to beta-lactamase producing organisms.

PCNs: Sensitivity

• Natural PCNs are effective against Streptococcus, some Enterococcus strains, and some non-penicillinase producing Staphylococcus strains.
• Aminopenicillins show greater activity against gram-negative bacteria due to their enhanced ability to penetrate outer membranes.
• They are used for gram-negative urinary and GI pathogens like Escherichia coli, Proteus mirabilis, Salmonella, some Shigella species, and Enterococcus faecalis.
• Active against common gram-negative respiratory pathogens: Moraxella catarrhalis and H. influenzae type B.
• Combining with beta-lactamase inhibitors broadens the spectrum.

Cephalosporins

• First generation: effective against gram-positive bacteria (S. aureus & s. epidermis).
• Second generation: effective against first-generation bacteria, plus Klebsiella and Proteus.
• Third generation: effective against a broader range of gram-positive and gram-negative bacteria, with enhanced activity against gram-negative bacteria.
• Fourth generation: more broad-spectrum and resistant to beta-lactamase compared to third generation; primarily targets gram-positive bacteria.
• Fifth generation (Ceftaroline): similar to third generation, plus active against MRSA.

Strep Throat (Group A Streptococcus) Antibiotic Therapy

• Primary treatments include beta-lactams (PCN V or Amoxicillin) or first-generation cephalosporins (cephalexin).
• Secondary treatments for patients with PCN allergies consist of Clindamycin or Azithromycin (note strep dosing).

Managing Antibiotic Side Effects

• Monitor illness symptoms to ensure improvement and review cultures.
• Provide patient education, including completing the entire course of treatment.
• Maintain the current treatment if effective, but change if symptoms worsen or culture results indicate a different antibiotic is needed.

"Watchful Waiting" for Children

• Observe for 48-72 hours without antibiotics in low-risk patients aged 2 and up who have non-severe illnesses; adequate pain management is essential.
• Low-risk patients are older than 2 years, have mild otalgia, and a temperature less than 39 degrees Celsius/102.2 F.
• Implement a safety net prescription or "Wait and See Prescription."

Otitis Media Treatment Failure

• Occurs at 48-72 hours (ages 2 and up).
• If initially treated with amoxicillin or another first-line therapy and had failure, use Augmentin or Ceftriaxone IM/IV for 3 days.
• For PCN allergies, use Clindamycin + a third-generation cephalosporin.

Tetracyclines

• Usage: treats bacterial infections.
• Indications: Doxycycline is the first-line therapy for C. trachomatis (chlamydia) and Ureaplasma urealyticum.
• Tetracycline and minocycline treat P. acnes.
• Some H. pylori regimens include tetracycline.
• Contraindications: Pregnant women (Category D), lactating women, or children aged less than 8 years.
• Use cautiously with patients who have renal or hepatic failure.
• Drug interactions: avoid antacids, zinc products, or magnesium-containing laxatives (separate by 2 hours).

CDC and ACIP Vaccine Guidelines

• Follow the recommended vaccine schedule for children (0-18 years) and adults.
• Use catch-up schedules as needed.
• Pregnant women have specific vaccination guidelines.
• Determine vaccines by age, interval for catching up, and medical conditions.
• Review vaccine type, frequency, interval, and considerations, and check contraindications/precautions.

MMR Vaccine

• Clinical Use: Prevents measles, mumps, and rubella.
• Dose: 0.5mL SQ.
• Contraindications: Neomycin allergy, pregnancy, immunocompromised conditions, and febrile illness (ok to give to egg allergy or lactating patients).
• Adverse Drug Reactions: Fever 7 to 12 days after vaccination, drug interaction with IG, oral steroids, and chemotherapy.
• Time Table: Two doses are administered. The first dose is at 12-15 months of age and the second dose at 4-6 years of age, or at least 4 weeks post the 1st dose
• One dose can be given to infants aged 6-12 months if traveling abroad but does not count as the 1st dose).

FluMist (Live Attenuated Influenza Vaccine)

• Clinical Use: Prevents Flu (live modified virus vaccine).
• Dose: Intranasal spray, 0.2mL split between each nare.
• Contraindications: Severe egg allergy, asthma, immunocompromised, and pregnancy.
• Adverse Drug Reactions: mild, such as nasal congestion, headache, sore throat, cough, and muscle aches.
• Time Table: Annually for healthy patients aged 2-49 years, ASAP in the fall.
• Children aged 2-8 years need 2 doses the first year.

Hep B Vaccine

• Clinical Use: Prevents Hepatitis B by stimulating anti-hepatitis B surface antigen antibodies; inactivated virus vaccine.
• Dose: Dependent on brand and age; usually IM, but can be given SQ.
• Contraindications: Yeast allergy, moderate or severe illness, and immunosuppression (give a larger dose in this case).
• Adverse Drug Reactions: Local reaction, fever, malaise.
• Time Table: Administered to all ages in 3 doses over 6 months (4 weeks between dose 1 and 2, 2 months between dose 2 and 3, and 4 months between dose 1 and 3).
• Newborns weighing less than 2,000 g receive the first dose within 24 hours of birth.

Varicella Vaccine

• Clinical Use: Prevents chickenpox; live virus vaccine.
• Dose: 0.5mL IM/SQ.
• Contraindications: Neomycin allergy, febrile illness, immunocompromised conditions, high-dose oral steroids, and pregnancy.
• Adverse Drug Reactions: Fever, rash, and injection site reaction.
• Time Table: Two doses: the first at 12-15 months and the second at 4-6 years. Adolescents and adults with no history of the vaccine should receive 2 doses at least 4-8 weeks apart.

Community Acquired Pneumonia (CAP) Pathogens

• The most common pathogen is Streptococcus pneumoniae, also most common in nursing homes, pregnant women, and pediatrics.
• Patients with underlying lung disease: Haemophilus influenzae and Moraxella catarrhalis are frequent pathogens, also Staph aureus, Mycoplasma pneumoniae, and viral pneumonia.
• Expect clinical improvement in 48-72 hours.

CAP Treatment Classifications

• Treatment based on Infectious Disease Society of America and the American Thoracic Society Consensus Statement (2007).
• Classification I: Previously healthy patients with no risk factors for drug-resistant S. pneumoniae – treat with a macrolide (azithromycin, clarithromycin, erythromycin) or doxycycline if allergic, for a minimum of 5 days.
• Classification II: Patients with risk factors requires respiratory fluoroquinolones (moxifloxacin, gemifloxacin, or levofloxacin) or a beta-lactam PLUS a macrolide (amoxicillin, amoxicillin/clavulanate, or cefpodoxime, cefuroxime, parenteral ceftriaxone followed by oral cefpodoxime), and Doxycycline can be used as an alternative to the macrolide.
• OP treatment for adults older than 60 with comorbidities is Ceftriaxone (Rocephin) 1g daily via IM or IV or Levofloxacin 500 mg IV daily then switch to oral therapy once patient tolerates oral medications.
• Classification III: Not admitted to ICU
• Classification IV: ICU patients.

CURB-65

• Confusion, uremia, RR, BP, 65 or older.

CAP Treatment During Pregnancy

• Macrolides Pregnancy Category B: erythromycin and azithromycin and Pregnancy Category C: Clarithromycin.
• Beta-lactam (PCNs) plus a macrolide if comorbidities or recent antibiotic use.

Pediatrics treatment

• Amoxicillin 80-90 mg/kg/day or Ceftriaxone 50mg/kg/day until able to take oral medicine; PCN Allergy-Clindamycin or macrolide.
• Infant with chlamydial PNA- Azithromycin 20 mg/kg/day for 3 days OR erythromycin 50mg/kg/day for 14 days.
• Older than 5 years with Mycoplasma PNA- Azithromycin 10 mg/kg on day 1, then 5 mg/kg on days 2-5, Clarithromycin 15 mg/kg/day in 2 divided doses or Erythromycin 40-50 mg/kg/day

Contraindications for Decongestants

• Children under 4 years old.
• Patients on concurrent MAOI therapy.
• Patients with severe hypertension or coronary artery disease.
• Limit caffeine and refrain from smoking.

Routine Medications for Newborns and Children (Eye, Ear, Nose, Throat)

• Newborns Prevention of ophthalmia neonatorum with erythromycin ointment within 1 hour of birth (prevents gonococcal, not chlamydial, conjunctivitis); gonococcal conjunctivitis requires IM or IV ceftriaxone; chlamydial conjunctivitis requires systemic erythromycin.
• Children with Bacterial conjunctivitis (children 3 months through 8 years are most likely Staphylococcus, Streptococcus, or Haemophilus conjunctivitis)- Ophthalmic antibiotics (Bacitracin, "-mycin," fluoroquinolones).
• Children <6 most likely H. influenzae (73%)- high dose amoxicillin-clavulanate.
• Blepharitis treated with gentle no-tears shampoo or erythromycin ointment.
• Hordeolum caused by S. aureus treated with antibiotic eye drops or ointment.
• Viral conjunctivitis treated with ophthalmic antibiotics; refer to ophthalmologist if herpes keratitis is suspected.

Ear Disorders

• Otitis Externa "swimmer's ear" is treated with combo products with corticosteroids (hydrocortisone) and antibiotic; acute treated with acid or alcohol drops (UNLESS PERFORATED TM) (4 drops for 7-10 days); chronic treated with mineral oil daily, steroid cream; malignant OE is rare but lethal is caused by pseudomonas aeruginosa is treated with parenteral antibiotics, an aminoglycoside and carbenicillin over 4-6 weeks, plus surgical debridement.

Otitis Media

• Caused by eustachian tube dysfunction leading to reflux of bacteria into the middle ear; S. pneumoniae, Nontypable H. influenzae, and M. catarrhalis are common pathogens.
• Treat: Wait and see for low risk patients over 2 years old.
• 1st line-Amoxicillin (dose at 80-90 mg/kg/day) OR combo drug amoxicillin-clavulanate 90 mg/kg/day;
• PCN allergy- any of the "-cef"(cephalosporins)
• Treatment failure-Augmentin or Ceftriaxone IM/IV
• Initial observation only for acute otitis media.

Nose Disorders

• Viral URI: most common rhinovirus (Typically lasts 7-9 days)
• Treat: Symptomatic care w/ fluids, antipyretics, nasal bulb suctioning in infants
• Caution: Decongestants ONLY in children age 4 and above avoid Systemic; pseudoephedrine, Topical” phenylephrine (neosynephrine) or oxymetazoline.
• Do NOT prescribe antibiotics.

Sinusitis

• 1st choice- Amoxicillin (dose at 80-90 mg/kg/day in high-risk children for 10-14 days); 45 mg/kg/day in low-risk children; for PCN allergy: cefdinir, cefuroxime, or cefpodoxime
• If worse after 72 hrs- Switch to augmentin if amoxicillin was first choice, or consider cefdinir, cefuroxime, cefpodoxime for children.

Throat Disorders

• Pharyngitis (strep throat) (Most common treatment bacterial cause: Group A strep confirmed by testing)- beta-lactams (PCN/Amoxicillin OR 1st gen cephalosporins like cephalexin).

Ophthalmic Beta Blockers for Glaucoma

• Treated by ophthalmologist.
• Safety- Monitor client for cardiac failure and hypotension; Do NOT abruptly stop, administer as prescribed
• Contraindications-Bradycardia/Heart Blocks, cardiogenic shock, CHF, ventricular dysfunction, poorly controlled DM, Raynaud’s disease, PVD, Pregnancy Category C, with other BBs

Influenza Vaccine (IM vs. Transnasal)

• Live attenuated Influenza (LAIV/Flumist) administered intranasally (virus replicates in nasal mucosa)
• Live modified virus w/ Contraindications of egg allergy, asthma, immunocompromised, and pregnancy; ADRs: mild, such as nasal congestion, sore throat, cough, and muscle aches.
• Dose- Annual 0.2mL split between each nare(age 2-49 yrs) , Child 2-8 yrs needs 2 doses first year
• Inactivated Influenza administered IM- Killed virus with 3 or 4 strain (Strains change annually based on predicated circulating strains) and Contraindications = egg allergy/anaphylaxis to flu vaccine, Guillain-Barre syndrome w/I 6 wks , or febrile

Attenuated Live Vaccines vs. Inactivated

• Live modified form of virus with Contraindications of pregnancy and immunocompromised.
• Drug Interactions-Antiviral drugs, separate IG admin from live vaccine
• Inactivated Vaccines =“Killed virus”/OK to coadmin use and use catch up schedule.

Community Acquired Pneumonia (CAP)

• Develops when an organism invades the lung parenchyma and its host defenses which are depressed results due to bacterial when it's lungs primary defense mechanisms are altered by a viral infection or immunological problems.
• Goals in treatment-return to baseline resp status, resolve fever in 2-4 days, resolution of leukocytosis by day 4 of treatment, resolve check xray in 4 weeks if returned to normal
• PT education on hydration, smoking cessation, rest, symptoms of worsening status, expected time line for improvement

Fluoroquinolones

• Use for Pneumonia treatment
• See CAP question above for more information.

Sinusitis Treatment (Children)

• Dx criteria Purulent rhinorrhea, facial/pain or pressure, nasal obstruction; children have subtle symptoms with mucus and puffy eyes with cough
• Treat/Adult: Amoxicillin/Children: 1st line 80-90mg/kg/day in high risk; 45mg/kg/day in low risk (10 to 14 days
• PCN Allergy- cefdinir, cefuroxime, or cefpodoxime or doxycycline, or respiratory fluoroquinolone (levofloxacin)
• Education-Saline drops/spray for secretions Topical decongestants/Corticosteroids for CHRONIC sinusitis

UTI

• Treatments Goals eradicate causative organism relief of symptoms/prevent the Recurrent Infection
• If Complicated - Symptoms lasting longer than 7 days, fever, shaking/chills/rigors, flank pain, other comorbidities need a longer treatment (5 to 7 days) using meropenem-vaborbactam (Vabomere) and Fluoroquinolones
• If Uncomplicated (3 days/adult and 10 days/children)
• 1st Line- Nitrofurantoin Macrobid/not recommended for children and infants/ pregnancy. 2nd Line-Cephalexin and beta lactams Amoxicillin and wide range of antibiotic rugs to treat, choose best on based on cultures
• Peds with febrile UTI treated Aggressively with IV ceftriaxone until afebrile, 10 days, culture after treatment(may need radiology workup)

Patient Education (Medications)

• Respiratory*
• Beta 2 Receptor Agonists – breath-actuated inhaler require inspiratory drive AND Xanthine Derivatives - take as prescribed and discuss toxicities and Theophylline elimination is influenced by diet.
• Anticholinergics- rinse mouth and Leukotriene Modifiers - Do not take if pregnant or nursing/Watch for drug interactions/neuropsychiatric events & depression ,
• Corticosteroids - Administration and MDI technique and ADRs - sore mouth or thrush
• Antihistamines- Caution and Report/cNS depressants and Antitussives - cough lasting longer than 7 days, increase fluid and quit smoking and if have excessive secretions
• Bacterial*
• Beta Lactams PCN - Resistance- complete RX /ADRs anaphylaxis and Beta Lactams Cephalosporins ADRs allergies/seizures/renal hepatic failure/complet Rx
• Fluoroquinolones Complicated ADRs - Black Box warning and Avoid in PREGNANCY d/t tendon rupture
• Lincosamide Clindamycin( ADRs-diarrhea, Macrolides and Azalides ADRs-dose related, GI and DIs and D/c or change iF Fidaxomicin,Linezolid well absorbed; Does not use CYP450 enzymes/ oral less expensive than IV version),
• Sulfonamides, Trimethoprim - Nitrofurantoin, Fosfomycin PT Ed – finishing course; ADRS educate resistance
• Tetracyclines: food, milk and calcium decreases absorption; dont take while pregnant/breastfeeding, not used for less than 8 yrs old.
• Glycopeptides Monitor Hearing and renal

Medications Administration

• Importance of taking medication daily
• Reporting of ADRs- peripheral neuropathy, hepatotoxicity, optic neuritis, ototoxicity, neutropenia/thrombocytopenia Viral Antivirals Good hydration, Antivirals for Hep C- meds daily and ADR/DIs
• Anthelmintics
• Albendazole (high-fat meal and backup contraception)
• Metronidazole (Metallic taste and avoiding alcohol is a must with both)
• Metallic taste, concurrent treatment of partner, avoid in first trimester and Signs of leukopenia
• Dose and Calculations for Medications*
• Calculations Amoxicillin First line for sinusitis 80/90 mg high and 45mg low
• < 2 years/no decongestants d/t viral symptoms - nasal bulb suctioning, reassurance, symptomatic

CY P450 Enzymes

• Can be inhibited, induced, ultra metabolized/rifampin-TB/inducer decrease effects decrease effects.

Stepwise Approach to Asthma

• First must determine severity then use step therapy chart
• Intermittent - short-acting beta 2agonists, as needed
• Mild Persistent w/ low-dose inhaled corticosteroid medication daily and beta agonists as needed
• Moderate Asthma - medium-dose inhaled corticosteroids or low-dose inhaled steroids plus long -Acting beta agonists
• Severe persistent - 5&6 - High dose ICS plus Long-acting and referral

LABA and SABA

• SE -Cardiac/CNS/Hyperglycemia Black box for LABA risk of Salmeterol/Formoterol outweigh and
• Montelukast*
• Medication used for Persistent and Exercise with Precautions not for acute

Asthma Considerations

• Minority device spacers and education decrease cost and morbidity and AVOID $T and Aclidinium
• Exercise for education for short acting 15/2, long acting 60/2 and leukoteine with mask and scarf
• Goals reduce impairment, prevent chronic symptoms and Reduce risk
• Safe Medications during Pregnancy*
• Inhaled Beta’s such as Butesonide is safest choice for profile

TB Drug Therapy Principles

• Regimens must have multiple drugs, regular with sufficient period with 2/6 months and test. RIPE – Rifampin, Isoniazid, Pyrazinamide, Ethambutol.
• COPD*
• Drug Treatment based on type and Oxygen and smoking
• Otitis Media and Externa*
• OM Preven Vaccinations and breast feeding and 1st AMOX 2/CEPH
• OE 1/2 Acetic