Urogenital/HIV Flashcards
Pol gene
Polymerase
- Reverse Transcriptase
- Integrase
- Protease
T. pallidium pertenue
Yaws
Immune Reconstructive Inflammatory Syndrome (IRS)
Paradoxical worsening of pre-existing infectious process following initiation of HAART in HIV pt
Streptococcus saprophyticus
Non-motile
Coagulase-ve, catalase -ve
Novobiocin resistant
Urease +ve (contributes to struvite formation)
ROS: uncomplicated UTI in young sexually active women aka “Honeymoon cystitis”
Kaposi’s Sarcoma
CD4 < 500
Etiology: HHV-8
Pathogenesis: tumor of blood vessel walls
ROS: pink/red/purple lesions on skin and mouth (can affect GIT and lungs too)
HPV
Condylomata acuminatum (6 and 11) mucosal membranes Oncogenic subtypes (16 and 18 via e6 and e7 inactivating RB and P53 respectively)
Env gene
Envelope glycoproteins
- gp41 - transmembrane glycoprotein (facilitates co-receptor binding w/ CCR5 on MΦ or CXCR4 on Th cells)
- gp120 - surface glycoprotein (binds to CD4)
UPEC virulence factors
Type I fimbriae: attach to mannosylated proteins (can detach by exposure to mannose aka mannose sensitive)
P adhesin: attach to glycophospholipids, assoc. w/ pyelonephritis
CD4 < 50
MAC (mycobacterium avian complex)
HSV-2
2 cause of cervicitis
Pathogenesis: cytolytic, fast replicating, latency in sacral ganglion, virus shed during replication
ROS: cluster of tender/painful lesions w/ tender lymphadenopathy
Diagnosis: Tzanck smear w/ multinucleated giant cells and Cowdry bodies (intranuclear inclusions)
HIV Pathogenesis
Syncytia formation, tropism for CD4 T-cells and MΦ, transported to LNs by MΦ or dendritic cells, downregulation of MHC, ag variation, masking of target epitopes
Leismhmania donovani
Transmission: usually sandfly vector but could be via needle sharing or blood transfusion too
ROS: disseminated visceral leishmaniasis (wt loss, fever, hepatosplenomegaly, anemia/pancytopenia)
Vulvovaginal Candidiasis
2 cause of vaginitis
Pathogenesis: directional hyphae growth (thigmotropism), dimorphism, biofilm formation, adhesins (Als3), hydrolases, siderophores
ROS: puritis, curdlike d/c, satellite lesion
Dx: KOH prep, pH in nml range
Trichomonis vaginalis
Flagellated protozoa w/ undulating membrane
Pathogenesis: lacks mitochondria (has hydrogenosome for anaerobic metabolism/fermentation)
ROS: usually asymptomatic; frothy d/c, gray or yellow-green color, strawberry cervix
Dx: motile trophozoites on microscopy
*increased susceptibility for HIV infection
Bacilliary angiomatosis
Etiology: Bartonella hensleae
Pathogenesis: obligate intracellular triggers proliferation and persistent infection of endothelial cells and RBCs
ROS: initially appears as purplish to bright red skin patches (resembles Kaposi’s Sarcoma)
CD4 < 100
Toxoplasma gondii Cryptococcus neoformans Cryptosporidium parvum CMV *CD4 from 50-100
Neisseria gonorrhoeae
Pathogenesis: Type IV pili for adhesion(ag variation for recurrent infection), IgA protease, β-lactamase, LOS (PMN infiltrate)
ROS (cervicitis): purulent d/c, dysuria, dyspareunia, PID
Dx: modified Thayer-Martin agar (DON’T refrigerate swabs); G-ve diplococci in dead PMNs
AIDS definition
- CD4 < 200
* 2 AIDS defining illnesses regardless of CD4 count
Non-specific Treponemal Screening tests?
VDRL and RPR: heterophile Ab’s against cardiolipin-cholesterol-lecithin ag
UPEC Pathogenesis
IBC: intracellular biofilm community
Quiescent reservoirs: metabolically inactive organism hiding in epithelial cells, the differentiation of the cell wakes the bacteria and this leads to recurrence of infections
Non-Hodgkin’s Lymphoma
Predisposing infections: HTLV-1, HCV, EBV
Pathogenesis: originates in lymphocytes usually in LNs
T. palladum carateum
Pinta
Paradoxical IRIS (AIDS pt)
Worsening of recognized pre-existing infection
Tuberculosis (AIDS assoc.)
1/3 of AIDS pt’s have TB too, leading COD in ppl living w/ AIDS
Nugent’s Criteria
Gram stain of vaginal swab: mixed flora w/ absent or low Lactobacilli indicxates BV
*Abnormal Nugent score = 10
Specific Treponemal Test:
FTA-ABS: fluorescent Treponemal Ab absorbed test
TP-PA
TPHA
MHA-TP
Pneumocystis jirovecii
CD4 < 200
Pathogenesis: CW contains chitin and glucan
ROS: interstitial pneumonitis w/ mononuclear infiltrate, dyspnea, nonproductive cough; extrapulmonary lesions in RES
Dx: bronchioalveolar lavage (BAL) w/ silver stain or toluidine blue (disc shaped clusters seen on microscopy)
CXR: ground glass
Klebsiella granulomatis
Clinical manifestation: ulcer
Pathogenesis: Donovan bodies (intracellular inclusions w/in macrophages)
ROS: beefy red suppurative PAINLESS ulcer w/ expanding borders that tend to bleed easily
Diagnosis: Giemsa stain (bc intracellular) or tissue-based culture would show “safety pin” appearance
T. paallidum endemicum
Bejel
Proteus vulgaris
Hyperflagellate (swarming motility)
Urease +ve
Phenylalanine delaminates (contributes to struvite stone formation)
H2S production
Dx: rose-like pattern on agar d/t type of motility
CMV (in AIDS pt)
Pathogenesis: est latent infection in mononuclear lymphocytes and stromal cells of BM, activated when CD4 levels drop
ROS: retinitis in eyes (can lead to blindness), GIT sx’s, pneumonia, other organs affected too
Klebsiella pneumoniae
#2 cause of uncomplicated UTIs and #3 cause of complicated UTIs Clinical manifestation: UTI, struvite stone (Urease +ve) Pathogenesis: large polysaccharide (mucoid) capsule, pili, LPS, carbapenemase
Chlamydophila trachomatis (L1-L3)
Clinical manifestation: Lymphogranuloma Venereum (LGV)
Pathogenesis: obligate intracellular (EB is infectious, RB is replicative)
ROS: painful buboes (nodules that ulcerated), enlarged painful LNs can form fistulas
MAC (complex)
AIDS defining illness complex of M. avium and M. intracellularae
ROS: cough, RES sx’s, night sweats, wt loses, fatigue, diarrhea, anemia
*CD4 < 50
HBV and HCV (in AIDS pt)
HIV + hepatitis = more likely to develop liver toxicity from meds (bc they’re metabolized in the liver)
CD4 < 500
Candida albicans
Kapok Sarcoma (HHV-8)
*CD4 from 200-500
Western Blot for HIV
Only used for screening blood from blood donors
HIV Lifecycle
- Binding to CD4 and CCR5 (or CXCR4 later in dz), fusion of membranes and virus injected into cell
- RT converts HIV RNA to dsDNA then transported to nucleus and integrated into host genome by integrase = provirus
- Provirus uses host RNA pol to transcribe mRNA makes HIV proteins and new virus self-assembles
- After budding from host cell protease cuts the proteins into smaller functional proteins
Bacterial Vaginosis
Pathogenesis: overgrowth of anaerobes d/t unbalanced pH bc of imbalance of Lactobacilli + biofilm formation by causative organisms
Etiology: Gardernella vaginalis
ROS: thin grey/milky white malodorous d/c (fishy smelling) and is adherent to vaginal walls
Composition of struvite stones?
Ammonium-magnesium-phosphate
Gag gene
Group specific antigens (core and capsid proteins)
- P17 - matrix protein
- P24 - capsid protein
- P7P9 - nucleocapsid protein
Treponema pallidum
Spirochete
Pathogenesis: endoflagellum (motility), hydrogenosome for fermentation (like Trichomonas), attaches to fibronectin, highly liphilic (immune evasion), immunopathogenic
Dx: darkfield microscopy (or screening and specific tests)
Clue cells
Sloughed epithelial cells coated w/ bacteria (namely Gardernella)
Salmonella
G-ve, motile, produces H2S, encapsulated
Transmission: reptiles, poultry, dairy
Pathogenesis: invades SI, travel through BM to lamina propria and enters blood stream
ROS: inflammatory diarrhea (more severe dz in AIDS pt)
Sequelae: chronic carrier state (shed from gallbladder)
Prevention: polysaccharide vaccine
Amstel Criteria
Diagnoses: bacterial vaginosis
Vaginal pH >4.5
Wet mount: clue cells > 20% per HPF
+ve amine or “whiff” test
Unmasking IRIS (AIDS pt)
Worsening of unrecognized pre-existing infection
Haemophilus ducreyi
Clinical manifestation: Chancroid
Epidemiology: Asia, Africa, Caribbean
Pathogenesis: cytolethal distending toxin kills T cells
ROS: ragged/soft PAINFUL ulcer, tender regional lymphadenopathy
Diagnosis: Factor X (fastidious growth) on Chocolate agar, “railroad tracks” arrangement of colonies
Lactobacilli
Protective against overgrowth of G-ve rods causing BV, produce lactic acid to maintain pH, H2O2 produced to maintain low pH
Cryptosporidium parvum
CD4 < 100
Transmission: recreational water
Pathogenesis: ingestion of oocyst that releases 4 motile sporozoites when it gets to SI, then it invades the epithelium and develops into trophzoite
ROS: profuse watery diarrhea (> 50 BMs per day), severe abd pn
Dx: oocysts on modified Ziegler-Neelson
Viral Load vs. CD4 Count
Viral load is cheaper and easier to monitor, suggests how rapidly dz occurs (monitors therapy), rises initially upon infection then goes down
CD4 < 200
Pneumocystis jirovecci (PCP) Histoplasma capsulatum Coccidiodes immitis JC virus (PML) *CD4 from 100-200
Chlamydophila trachomatis (D-K)
Clinical manifestation: #1 cervicitis, #2 urethritis (non-gonococcal), #2 PID
Pathogenesis: obligate intracellular; EB (infectious) and RB (replicative)
ROS: watery d/c, dysuria (burning) [men - itchy penis]
Dx: NAATs (or Giemsa? cuz intracellular)
Syphilis
Primary: painless chancre
Secondary: condylomata lata (highly infectious), copper/bronze rash involving palms and soles
Tertiary: tabes dorsalis, CVS and CNS sx’s
Mycoplasma genitalium
3 urethritis (non-gonococcal)
Structure: lacks CW, has sterols in outer membrane
Pathogenesis: MgPa tip adhesins, produces H2O2 and superoxides (damage tissue), lipoproteins (evade host defenses)
ROS: urethritis (non-specific sx’s)
Toxoplasma gondii
CD4 < 100
Transmission: ingestion of oocytes via cats or undercooked meat
Pathogenesis: reactivation of cysts
ROS: CNS sx’s (focal encephalitis w/ HA, fever, confusion, motor weakness)
Dx: proliferating tachyzoites surrounded by liquefactive necrosis
CT: ring enhancing lesions in brain
