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IM - ZOONOSES AND ARTHROPOD-BORNE DISEASES

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tonystep1's version from 2017-08-11 02:16

ZOONOSES AND ARTHROPOD-BORNE DISEASES CLINICAL FEATURES

Question Answer
Lyme Disease Stage IStage 1-early, localized infection // Erythema migrans is the hallmark skin lesion at site of the tick bite. Characteristically it is a large, painless, well-demarcated target-shaped lesion, commonly seen on the thigh, groin, or axilla // Multiple lesions signify that hematogenous spread has occurred (see below).
Lyme Disease Stage IIStage 2-early, disseminated infection // intermittent flu-like symptoms, headaches, neck stiffness, fever/chills, fatigue, malaise, musculoskeletal pain // After several weeks, about 15% of patients develop one or several of the following - Meningitis , Encephalitis , Cranial neuritis , and Peripheral radiculoneuropathy (motor or sensory) // 8% cardiac issues
Lyme Disease Stage IIIStage 3-late, persistent infection (months to years after initial infection) // Arthritis-This occurs in 60% of untreated patients; it typically affects the large joints (especially knees). // Chronic CNS disease-subacute, mild encephalitis, transverse myelitis, or axonal polyneuropathy. // Acrodermatitis chronica atrophicans (a rare skin lesion)-reddish-purple plaques and nodules on the extensor surfaces of the legs.
Rocky Mountain Spotted FeverIt classically presents with a sudden onset of fever, chills, malaise, nausea, vomiting, myalgias, photophobia, and headache. // Papular rash usually appears after 4 to 5 days of fever. Rash starts peripherally (wrists, forearms, palms, ankles, and soles) but then spreads centrally (to the rest of the limbs, trunk, and face) It becomes maculopapular, and eventually petechial // It may lead to interstitial pneumonitis
Malaria by P.falciparumSymptoms may include fever and chills, myalgias, headache, nausea, vomiting, and diarrhea. // P falciparum-fever is usually constant
Malaria by P ovale or vivaxSymptoms may include fever and chills, myalgias, headache, nausea, vomiting, and diarrhea. // P ovale and P viva.x-fever usually spikes every 48 hours
Malaria by P malariaeSymptoms may include fever and chills, myalgias, headache, nausea, vomiting, and diarrhea // P malariae-fever usually spikes every 72 hours
RabiesThe incubation period typically ranges from 30 to 90 days, but varies considerably // Symptoms (in progressive order) - Pain at site of bite - Prodromal symptoms of sore throat, fatigue, headache, nausea, ancl/or vomiting - Encephalitis-Confusion, combativeness, hyperactivity, fever, and seizures may be present - Hydrophobia-inability to drink, laryngeal spasm with drinking, hyper-salivation ("foaming at mouth " ) , usually progresses to coma and death // Some patients may present with ascending paralysis
LeptospirosisTransmitted by contaminated water // Anicteric - rash LAN, inc LFTs // Icteric - renal and/or liver failure
EhrlichiosisTransmitted by Tick bite // Fever, chills, malaise +-rash //Complications include renal failure , GI bleeding
TularemiaTransmitted by Tick bite , animal bites , handling carcass //Fever , headache, nausea ; ulcer at site of tick bite ; painful LAN
Q FeverTransmitted by Blood, ingestions of infected milk, inhalation // Acute - constitutional symptoms nausea vomiting // Chronic - endocarditis
Cat Scratch diseaseTransmitted by Scratch from flea infested cat // LAN or lymphadenitis ; systemic symptoms rare
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DIAGNOSIS OF ZOONOSES AND ARTHROPOD BORNE DISEASES

Question Answer
Lyme DiseaseClinical diagnosis-In early, localized disease, documented erythema migrans in a patient with a history of tick exposure in an endemic area obviates the need for laboratory confirmation. Treat empirically.// Serologic studies-most important tests to confirm a clinical suspicion of Lyme disease ELISA is used to detect serum IgM and IgG antibodies during the first month of illness.
Rocky Mountain Spotted FeverDiagnosis is primarily clinical. Laboratory abnormalities may include elevated liver enzymes and thrombocytopenia
MalariaIdentify organism on peripheral blood smear // Blood smear must have Giemsa stain
RabiesVirus or viral antigen can be identified in infected tissue. Virus can be isolated in saliva as well // Four-fold increase in serum antibody titers // Identification of Negri bodies histologically // PCR detection of virus RNA
LeptospirosisIsolation of spirochetes in blood or urine CTX.
EhrlichiosisClinical diagnosis , confirmed by serology Ehrlichia spp. (intracellular gram negative bacteria)
TularemiaIsolation of Francisella tularensis (small gram negative bacillus ) in blood or wound CTX.
Q feverconfirmed by serology of Coxiella burnetti (gram negative organism) and CXR show multiple opacities in acute illness
Cat scratch diseaseSerologic confirmation of Bartonella henselae ( gram negative bacillus) diagnosis is clinical
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TREATMENT OF ZOONOSES AND ARTHROPOD BORNE DISEASES

Question Answer
Lyme Disease Early localized diseaseIf it is confined to the skin, 10 days of antibiotic therapy is adequate. // If there is any evidence of spread beyond the skin, extend treatment to 20 to 30 days.
For early Lyme diseaseOral doxycycline (for 2l days)-contraindicated in pregnant women and in children l2 years of age or older // Amoxicillin and cefuroxime are alternative agents // Erythromycin may be given to pregnant patients with penicillin allergies. // extend treatment to 30-60 days for complications
Rocky Mountain Spotted FeverDoxycycline-usually given for 7 days; given intravenously (IV) if the patient is vomiting // CNS manifestations or pregnant patients-give chloramphenicol
MalariaUse chloroquine phosphate unless resistance is suspected // If chloroquine resistance is suspected, give quinine sulfate and tetracycline // P falciparum infection may require IV quinidine and doxycycline // Relapses can occur in P. vivax and P. ovale infections add 2 week regimen of primaquine phosphate // Prophylaxis to endemic areas use Mefloquine.
Rabies guidelinesClean the wound thoroughly with soap // For wild animal bites (e.g. , bat or raccoon), the animal should be captured if possible, destroyed, and sent to a laboratory for immunofluorescence of brain tissue // If a patient was bitten by a healthy dog or cat in an endemic area, the animal should be captured and observed for 10 days. // Administer the human rabies immunoglobulin into the wound as well in the gluteal region and dminister the antirabies vaccine in three IM doses into the deltoid or thigh over a 28-day period
LeptospirosisOral antibiotics:tetracycline or doxycycline; if severe, IV penicillin G
EhrlichiosisOral tetracycline or doxycycline :±: 1 week
TularemiaIM streptomycin or gentamicin
Q feverAcute: doxycyclineor fluoroquinolone
Cat scratch diseaseUsually self-limited; if severe, oral doxycycline or ciprofloxacin
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