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Atypical Organisms. Mycoplasmas. Characteristics Lack cell walls Pleomorphic (fried egg) NM FA-Obligate anaerobes Examples M. genitalium M. pneumoniae M. hominis Diseases Pneumonia Urogenital infections. Rickettsias. GN (very little PG) Intracellular parasites Aerobic
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Mycoplasmas Characteristics Lack cell walls Pleomorphic (fried egg) NM FA-Obligate anaerobes Examples M. genitalium M. pneumoniae M. hominis Diseases Pneumonia Urogenital infections
Rickettsias • GN (very little PG) • Intracellular parasites • Aerobic • Slow reproduction • Cell lysis for release • Arthropod vectors • Species • R. rickettsii • R. typhi • R. prowazekii
RMSF • R. rickettsii • Dermacentor tick • STD for ticks • Salivary gland host blood • Humans, rodents • Damage endothelium • CS • F/N/V/myalgia • Spotted rash, pettechiae • Gangrene, paralysis • Encephalitis, death • Dx : IFA, agglutination • Tx: AB, remove tick
Epidemic Typhus • R. prowazekii • Pediculis louse • Human host • CC/CS • Fever, depression • Rash • Dx: IFA • Tx: AB • Pv: hygeine, sanitation
Murine (Endemic) Typhus • R. typhi • Flea (rat, cat) • Rodent (murine) reservoir • Human exposure to fleas • CC/CS • Fever, headache, myalgia • Rash on trunk and chest • Dx: IFA • Tx: AB • Pv: Flea control
Scrub Typhus • Orientia tsutsugamushi • Red Mites (chiggers) • Rodents and Humans • Pacific • Asia, Japan • Australia • CS • Fever, headache • Myalgia, lymphadenopathy • Rash on trunk • Tx: Ab • Pv: mite control, repellent
Ehrlichia and Anaplasma • Emerging disease (1987) • Intracellular parasite in WBC • Hard Ticks • Lone Star (Ambylomma) • Deer (Ixodes) • Dog (Dermacentor) • Species • E. chaffeensis • E. equi (Anaplasma) • CC/CS: • Fever, rash, leukopenia • Dx: IFA • Tx: AB • Pv: Tick control
Chlaymdia • Intracellular parasite • No cell wall • 2 forms during development • Elementary bodies (EB) • Dormant, infective • Reticulate bodies • Intracellular inclusions • Species • C. trachomatis • C. pneumoniae • C. psittaci
Chlamydia trachomatis • Reportable STI • Human cells with EB receptors • Respiratory • Female repro • Lower GI (rectum) • CS • Ocular lesions (trachoma) scar cornea blindness or • Lymphogranuloma • Buboes • Genital sores • Urethritis, vagninitis, proctitis • Dx: Giemsa stain, culture • Tx: AB • PV: safe sex
Chlamydia pneumoniae • Community acquired • Droplet transmission • CS • Sinusitis • Bronchitis • Chronic cough • Pneumonia • +/- atherosclerosis • Dx: FA • Tx: AB
Chlamydia psittaci • Zoonotic • Parrot fever • Aerosolized EB in feces • CS • Flu like symptoms • Pneumonia • Dx: serology • Tx: AB • Pv: husbandry • Quarantine
Spirochetes • GN, helical/coiled • Endoflagella • Corkscrew shape • Genera • Treponema • Borrelia • Leptospira
Treponema • Human pathogen • Obligate intracellular parasite • T. pallidum pallidum • Fastidious • CH2O use • Host: FA, Protein, enzymes • Double membrane • 2 flagella • Lack of surface proteins • STI (STD) • Tx : AB [penicillins] • Syphilis
Syphilis • CS/Stages • 1 : Primary • Active • Blister • 2 : Disseminated • Latent • Rash • 3 : Tertiary • CV (aneurysms) • NS (meninges) • Skin/Bone (Gummas) • 4: Congenital • Fetus (stillborn) 1 2 3
Treponema pallidum … • T. p endemicum • “Bejel” • MM • gummas • T. p pertenue • “Yaws” • Skin: granular, draining tracts • T. carateum • “Pinta” • Skin papules flat Hyper & depigmentation
Borrelia • Spirochete • Endoflagella • Extracellular parasite • Species and Strains • B. burgdorferi • B. andersoniii • B. japonica • B. valaisiana • B. lonestari • B. turcica • B. recurrentis • Genetics • Linear chromosome • Plasmids • Zoonotic • Arthropods • Ticks • Fleas • Lice • Dx: IF, serology, organism in blood
B. burgdorferi • GN spirochete • Deer mice host, deer • Hard tick (Ixodes) spread (3x) • Lyme’s disease • CS • Bull’s eye rash • Myalgia • Neuropathy • Arthralgia Chronic Arthritis • MO IL-1, IL-6 TH 17 cells • Dx: serology • Tx: AB • Pv: tick control, repellent
Relapsing Fever • Borrelia recurrentis • Arthropod vector • Lice (human) • Soft Tick • Rodent reservoir • Humans • CS: fever, malaise • Dx: Blood smear • Tx: AB • Pv: vector control
Leptospira • Spirochete • Zoonotic • Species • L. interrogans (humans) • L. …….. • Transmission • Contam Urine water • Primary Hosts • Rats • Mice • Moles • Secondary Hosts • Dogs • Deer • Rabbits • Raccoons • Skunks • Opossums
Leptospirosis • CS • N/V/F/headache • Pneumonia • Migrates through tissues • Renal • Meningitis • Liver failure (Weil’s Ds) • Respiratory distress • Dx: • Giemsa stain • titers • Tx: • AB • fluids • Pv: vaccinate animals NA Epidemic ~1620 (Pilgrims) Out breaks: Civil War, WWI, WWII