Skin Rash Diseases PDF

SKIN RASH Disease Causative agent Pathogenesis Manifestations Diagnosis Treatment Prevention Image Lyme Disease Borrelia invades skin (then L: Erythema migrans​ Known Doxycycline Avoidance of Bull’s eye rash​...

SKIN RASH Disease Causative agent Pathogenesis Manifestations Diagnosis Treatment Prevention Image Lyme Disease Borrelia invades skin (then L: Erythema migrans​ Known Doxycycline Avoidance of Bull’s eye rash​ burgdorferi heart, CNS, joints) exposure Ceftriaxone ticks S: Clinical tick Bell palsy presentation fever serology​ arthritis in type 3 hypersensitivity Erysipelas Streptococcus M proteins dermal pain Catalase (-) Penicillin Raised facial pyogenes fever Gram (+) Erythromycin butterfly wing rapid spread Bacitracin skin edema sensitive lymphadenopathy Scarlet fever Streptococcus erythrogenic toxin fever (same as Penicillin Erythematous rash pyogenes trunk + neck above) Clindamycin (sandpaper-like) extremities strawberry tongue TSS Staphylococcus superantigen TSST acute onset temp. 39C < Cloxacillin Generalized aureus (TSST) fever sys. 90mmHg *Rifampicin/fusidi maculopapular rash hypotension diffuse c acid (faster Predispositions: multiorgan failure macular penetration to skin abscess myalgia erythema inflamed tissues) vaginal infections involvement of organ systems SSS Staphylococcus desquamation Neonate: Catalase (+) Nafcillin early lesions: pale + aureus (pyrogenic exfoliatins Ritter/Lyell’s Gram (+) Oxacillin flaccid shallow bullae exotoxins - syndrome Coagulase Vancomycin severe: scalded exfoliatins) Trunk & neck (+) cocci (penicillin allergic) extremities Nikolsky’s sign (+) Secondary syphilis Treponema endotoxin fever microscopy: penicillin pallidum lymphadenopathy exudate from doxycycline splenomegaly chancre erythromycin Predispositions: CONDYLOMATA DF/UV IV drug abuse (in LATA (anogenital) microscopy females) serology: ​ ​ Non specific: VDRL , RPRT Specific: FTA-ABS, MHA-TP Rocky mountain Rickettsia endotoxin ankles and wrists Serology Doxycycline Avoidance of Generalized spotted fever rickettsii infects endothelial fever Chloramphenicol ticks maculopapular rash cells in lung, spleen, respiratory Dog tick, wood tick brain and skull symptoms splenomegaly/lymph -adenopathy/shock can follow Epidemic typhus Rickettsia endotoxin trunk extremities Serology Doxycycline Delousing by Generalized prowazekii infects vascular fever Chloramphenicol insecticides maculopapular rash endothelium in skin arthralgia Formaldehyde-​ (after 5-9 days) Life cycle: can lead to severe inactivated in lice gut → lice meningoencephalitis typhus vaccine excrete organism during defecation CAN → infected feces REACTIVATE enter scratch TO BRILL-​ wound ZINSSER DISEASE Body lice: Pediculus humanus Scrub typhus Orientia resembles epidemic Characteristic Doxycycline No vaccine Macular-papular rash tsutsugamushi typhus feature: Chloramphenicol avoid exposure Eschar (below) fever eschar to chiggers Life cycle:​ severe headache (punched out Larvae (chiggers) lymphadenopathy ulcer with →reservoirs splenomegaly central through CNS complications necrosis) transovarial transmission → vectors → infects human and rodents Mites Molluscum Molluscum Virus enters through no long term NO SPECIFIC Wart-like bumps contagiosum contagiosum virus break in skin problems TREATMENT (Mollusca) (MCV) - poxvirus mollusca leaves no mark dsDNA enveloped Rubella Rubella virus - Droplet mild fever NO SPECIFIC MMR vaccine rubivirus transmission from swollen, tender TREATMENT nose/throat lymph nodes (+)ssRNA congenital rash begins on face enveloped transmission then spreads downwards itchy rash (later sheds in flakes) Measles Measles virus - contagious resp. hacking cough Koplik’s spots NO SPECIFIC MMR vaccine morbillivirus, infection runny nose (small red TREATMENT paramyxoviridae high fever spots with red eyes blue-white (-)ssRNA rash begins on centers in enveloped forehead then mouth) downwards Roseola HHV (type 6,7) Droplet high fever NO SPECIFIC transmission mild upper resp. TREATMENT Viral illness in dsDNA illness children (6 enveloped fever ends → rash months-2 years) develops rash behind from trunk Chickenpox Varicella zoster Airborne fever Red bumps, NO SPECIFIC Chickenpox virus (VZV) transmission headache blisters. Scabs TREATMENT vaccine droplet sore throat all appear at transmission stomach ache ONCE CAN rash all over the everywhere REACTIVATE body INTO SHINGLES Shingles (below) Infectious Epstein-Barr virus droplet flu-like symptoms NO SPECIFIC mononucleosis transmission fever TREATMENT swollen lymph nodes HFMD Coxsackie A16 droplet fever NO SPECIFIC Enterovirus 71 transmission (also painful red blisters TREATMENT stool) on hands, feet, mouth (+)ssRNA and diaper area Non-enveloped Erythema Parvovirus B19 congenital 30% asymptomatic Slapped NO SPECIFIC Lacy pattern infectiosum transmission slight cheek TREATMENT erythema droplet fever/headache syndrome transmission  VIRAL HAEMORRHAGIC FEVER Disease Causative agent Pathogenesis Manifestations Diagnosis Treatment Prevention Image Dengue Dengue virus mosquito bites → BIPHASIC: Known NO SPECIFIC Dengue DENV particles (DENV) infect the fibroblasts DF: exposure to TREATMENT vaccine (children and dendritic cells nausea dengue-ende 9-16 in endemic Aedes mosquito spreads to lymph vomiting mic areas (2 areas) nodes, spleen, liver maculopapular rash weeks) Mosquito (+)ssRNA high viremia ​ aches and pains rash extends control enveloped from trunk DHF/DSS: thrombocytopenia Investigations: hypovolemic shock NS1 antigen hemorrhagic (+) manifestations: anti-DENV petechiae, purpura, IgM antibody ecchymoses (+) viral RNA (+) Yellow fever Yellow fever virus mosquito bites → asymptomatic/mild Known NO SPECIFIC Yellow fever YFV particles (YFV) infect the dendritic symptoms exposure to YF TREATMENT vaccine (those cells sudden onset of endemic areas travelling to Aedes/Haemagogus spreads to lymph fever/chills/severe Clinical endemic area) mosquito nodes, spleen, headache/fatigue features Mosquito kidney, bone brief remission then control mosquitoes feed on marrow, more severe form of Investigations: primates (including myocardium disease anti YFV IgM humans) → severe antibody (+) primate-primate hepatic/renal injury Severe symptoms: viral RNA (+) transmission apoptosis of Abdominal pain hepatocytes Jaundice S.america, Africa cytokine storm renal failure due to severe melena + (+)ssRNA immune activation hematemesis (GI enveloped haemorrhage) Ebola virus disease Ebolavirus virus enters severe hemorrhagic Known NO SPECIFIC Ervebo vaccine EV particles through break in fever (can resemble exposure TREATMENT no contact with Infected fruit membranes → other VHF) within 21 days contaminated bats/body fluids infects a range of abrupt onset of surfaces from an infected cells fever, severe Investigations: human severe damage to headache, malaise, viral RNA (+) liver, spleen, lymph myalgia, abdominal viral antigen (-)ssRNA, nodes discomfort (+) filamentous DIC rash detection of enveloped high viremia after nausea, vomiting, IgM (acute) death prostration, anuria (2-3 days) Marburg virus Marburg (same as EVD) (same as EVD) (same as EVD) NO SPECIFIC NO VACCINE MV particles disease virus/Ravn virus TREATMENT MOT similar to EVD/bats (-)ssRNA, filamentous enveloped Lassa fever Lassa virus​ virus enters skin often Known NO SPECIFIC NO VACCINE LASV ​ through asymptomatic/mild exposure TREATMENT Rodent control Multimammate rat - abrasions/inhalation slight fever, malaise, Ribavirin Mastomys natalensis viremia headache Investigations: DIC only at viral RNA (+) Rat shed virus in terminal phase Severe: viral antigen urine → hepatocellular haemorrhaging in (+) contamination/inges necrosis gums/eyes/nose IgM (+) tion → spreads platelet neuropathy: through body fluids dysfunction hearing loss, Post-mortem: endothelial tremors, encephalitis ecchymoses Bisegmented (+/-) damage petechiae ssRNA enveloped Hantavirus disease Hantavirus trigger immune 5 stages: common in NO SPECIFIC NO VACCINE Hantavirus responses winter TREATMENT Rodent control Rodent-borne (non-cytopathic) Febrile: known Ribavirin endothelium intense headache, exposure dialysis New world dysregulation → backache, fever, [America] : HPS vascular chills, myalgia Investigations: Old world [Eurasian] hyperpermeability petechial rash viral RNA (+) : HFRS platelet damage (signs of viral antigen renal tubules haemorrhage) (+) Rodent damage IgM (+) saliva/urine/feces Hypotensive: → rodent-human Sudden + extreme transmission hypotension zoonotic albuminuria (foaming urine) 3 segmented (-)ssRNA Oliguric: Enveloped Acute kidney injury oliguria (reduced urine output) renal dysfunction (can lead to renal failure) Diuretic: increased urine output gradual recovery Convalescent: resolution HFRS > HPS CCHF Nairovirus DIC 4 stages common NO SPECIFIC NO VACCINE organ failure during TREATMENT insect Ixodid (hard) ticks impaired/excessive Incubation: right spring/winter Ribavirin repellents clotting after bite thrombo-​ Tick bites hepatic failure cytopenia domestic/wild Pre-hemorrhagic: leukopenia mammals → direct fever, malaise, GI elevated liver contact with symptoms enzymes blood/tissue of decreased infected animals → Haemorrhagic: platelet count human-human fluid facial flushing decreased transmission petechiae/ecchy-​ fibrinogen (reuse of moses increased needles/contaminat hematemesis aPTT ed medical supplies) melena epistaxis Investigations: (-)ssRNA (nosebleed) viral RNA (+) enveloped haematuria viral antigen haemoptysis (+) IgM (+) Rift valley fever Rift valley fever liver + mild/non-specific flooding NO SPECIFIC NO VACCINE virus reticuloendothelial symptoms (such as elevated liver TREATMENT (for humans) organs undifferentiated enzymes insect Insect bites (mainly (cytopathology) febrile illness) reduced repellents Culex/Aedes destruction of platelet + Hb avoid mosquitoes) hepatocytes Severe: unsafe/raw/​ splenomegaly Confusion, coma, Investigations: undercooked Direct contact with encephalitis stupor (due to viral RNA (+) animal products blood/tissue of encephalitis) IgM (+) livestock infected animal bleeding from vaccination consumption of gums, nose, GI (due raw/undercooked to haemorrhaging) meat retinitis zoonotic (-)ssRNA enveloped  Helminths Disease Causative agent Pathogenesis Manifestations Diagnosis Treatment Prevention Image Filariasis/​ Wuchereria toxins mostly elevated IgE DOC: mosquito Elephantiasis bancrofti excessive asymptomatic eosinophilia Diethylcarbamazin repellents Brugia malayi production of shortness of e Brugia timori histamine breath, wheezing Microscopic: blockage of lymph Microfilariae Microfilariae but not Mosquito bites nodes → infiltration filarial fever: spotted (WB) adult : of immune cells Rigors and tremors nocturnal Ivermectin lymphangitis Shivering Flushed face Nasal discharge High fever RECURRING FEVER ATTACK (BM) skin thickening hydrocele (swelling of scrotum) Cutaneous Larva Ancylostoma larvae cannot creeping clinical DOC: washing Migrans/Ground braziliense penetrate into eruption (leads to presentation Albendazole hands itch Ancylostoma deeper layers of the itching papules general caninum skin that shift) when lesions are preventive present on outer Loeffler’s few: measures Parasite eggs are layers of the skin syndrome Freezing eruption passed in feces of with ethyl chloride infected animal into soil → contamination on contact → penetrate into skin River blindness Onchocerca volvulus adult worms live in Onchocerca Microscopic: DOC: larvicides subcutaneous nodules (from skin snip) Ivermectin insect Day biting female tissues and are hanging groin repellents black flies (Simulium) encapsulated in (due to lymphatic Surgical excision if nodules drainage) nodules are on head pelvic/head/neck river blindness lymphangitis dermatitis (antigens released from killing microfilariae) biopsy (ocular manifestation) PCR of skin snip Cercarial Schistosoma have glands with papular skin rash known exposure Corticosteroid do not swim in dermatitis/​ haematobium digestive enzymes (areas immersed in to water cream unsafe/marshy Swimmer’s itch Schistosoma and chemicals to water) skin biopsies cool compress water japonicum invade host by anti-itch lotion towel Schistosoma breaking the skin dry/shower mansoni cercariae die after immediately invasion but trigger after leaving Water snails, ducks immune response → the water rashing do not attract birds to swimming areas