XI - Other Bacteria Flashcards
Zoonoses
Brucella abortus, Francisella tularensis, Yersinia pestis, Pasteurella multocida
Small gram (-) rods without a capsule, contaminated dairy, direct contact, undulating fever
Brucellosis
Brucellosis: Cow
B. abortus
Brucellosis: Dog
B. canis
Brucellosis: Goat/Sheep
B. melitensis
Brucellosis: Sheep
B. ovis
Brucellosis: Treatment
Doxycycline + Rifampin
Small gram (-) rods, reservoir - rabbits, deer, rodents, transmission - ticks (Dermacentor), aerosols, contact, ingestion
Francisella tularensis (Tularemia)
Francisella tularensis: Treatment
Streptomycin, Gentamicin
Most virulent bacteria
Yersinia pestis
Small gram (-) rods with bipolar (safety pin) staining, reservoir - rodents, transmission - flea bite, inhalation
Yersinia pestis
Buboes, cutaneous hemorrhage
Yersinia pestis
Bubonic, Pneumonic and Septicemic Plague
Yersinia pestis
Yersinia pestis: Treatment
Streptomycin, Tetracycline
Short encapsulated gram (-) rod that exhibits bipolar staining, buttery colonies with musty odor due to indole production, osteomyelitis, reservoir - cats and dogs, transmission - animal bites
Pasteurella multocida
Pasteurella multocida: Treatment
Penicillin G
Aerobic, acid-fast rods, Ziehl-Neelsen (hot), Kinyoun (cold), high lipid content, mycolic acids, wax D, produces catalase and niacin, slow-growing on Löwenstein–Jensen medium (1 mo.), luciferase assay for drug resistance
Mycobacterium tuberculosis
Mycobacterium tuberculosis: Location
lungs
Mycobacterium tuberculosis: Transmission
respiratory droplets from coughing
TB Virulence Factors: Prevents phagosome-lysosomal fusion
Exported Repetitive Protein (Sulfatides)
TB Virulence Factors: Most important VF, prevents leukocyte migration
Cord Factor
TB Virulence Factors: Elicits delayed hypersensitivity
Tuberculin Surface Protein (Purified Protein Derivative - PPD)
Mycobacterium tuberculosis: Lesions
exudative, granulomatous
Central area of Langhan’s giant cells surrounded by a zone of epithelioid cells, tubercle is a granuloma surrounded by fibrous tissue that has undergone central caseation
Mycobacterium tuberculosis Granulomatous Lesions
TB Phase of Infection: Middle-lower lobes, subpleural granuloma, CLAD, radiologically detectable calcification
Primary Complex
TB: Subpleural Granuloma
Ghon’s Focus
TB: Subpleural Granuloma + Associated LN
Ghon’s Complex
TB: Radiologically Detectable Calcification
Ranke’s Complex
TB Phase of Infection: Apices (Simon’s Focus), cicatricial changes, subpleural blebs, cavitation, fibrosis, nodules, secondary colonization with A. fumigatus (fungus ball), pneumothorax
Reactivation TB
Reactivation TB: X-ray Findings
apices (Simon’s Focus), cicatricial changes, subpleural blebs, cavitation, fibrosis, nodules
PPD: HIV (+), AIDS, old TB, immunosuppressed
> 5 mm
PPD: High-risk Population
> 10 mm
PPD: Low-risk Population
> 15 mm
TB: Spectrum of Disease
pulmonary TB, miliary TB, scrofula (CLAD), erythema nodosum, TB meningitis, spondylitis (Pott’s), GI TB (ileocecal), renal TB, abdominopelvic TB
Cough ≥ 2 weeks ± local/constitutional symptoms
PTB Suspect
PTB: Local Symptoms
hemoptysis, chest pain, dyspnea
PTB: Constitutional Symptoms
night sweats, weight loss, anorexia, fever, chills, fatigue, malaise
Specimen: PTB
sputum AFB x 3
Specimen: TB Lymphadenitis
excisional biopsy
Specimen: TB Effusion
pleural fluid studies
Specimen: Genitourinary TB
urine AFB (PCR)
Specimen: Spinal TB (Pott’s)
tissue biopsy
Specimen: Abdominal TB
barium studies (intestinal), CT (extraintestinal), peritoneal fluid studies (AFB, Q/Q)
Specimen: TB Meningitis
CSF studies (AFB, Q/Q)
Specimen: TB Pericarditis
pericardial fluid studies (AFB, Q/Q)
PTB Treatment: New smear (+), new smear (-) with extensive disease, new severe extrapulmonary TB
Category I - Initiation: 2 HRZE, Continuation: 4 HR
PTB Treatment: Sputum smear (+), relapse, treatment failure, defaulter
Category II - Initiation: 2 HRZES + 1 HRZE, Continuation: 5 HRE
PTB Treatment: New smear (-) other than Cat. I, new less severe extrapulmonary TB
Category III - Initiation: 2 HRZE, Continuation: 4 HR
Mycobacterium tuberculosis: Prevention
droplet precautions, BCG vaccine limits extent of disease
Uses of BCG (Bacillus Calmette-Guerin) Vaccine
TB prevention, urinary bladder CA treatment (intravesicular infusion)
Cause pulmonary disease in immunocompromised hosts (CD4 < 50)
Mycobacterium Avium-Intracellulare Complex (MAI/MAC)
Mycobacterium Avium-Intracellulare: Treatment
Azithromycin
Aerobic acid-fast rods, can’t becultured in vitro (mouse footpad, armadillo)
Mycobacterium leprae (Hansen’s coccus spirilly)
Mycobacterium leprae: Location
humans, armadillos
Mycobacterium leprae: Transmission
prolonged exposure to nasal secretion of patients with the lepromatous form
Leprosy: One or few lesions
Tuberculoid
Leprosy: Little tissue destruction
Tuberculoid
Leprosy: Few acid-fast bacilli
Tuberculoid
Leprosy: Low transmission rate
Tuberculoid
Leprosy: Cell-mediated response to M. leprae
Tuberculoid
Leprosy: Lepromin skin test (+)
Tuberculoid
Leprosy: Many lesions
Lepromatous
Leprosy: Marked tissue destruction
Lepromatous
Leprosy: Many acid-fast bacilli
Lepromatous
Leprosy: High transmission rate
Lepromatous
Leprosy: Reduced/Absent cell-mediated response to M. leprae
Lepromatous
Leprosy: Lepromin skin test (-)
Lepromatous
Hypopigmented plaques, thickened superficial nerves, significant anesthesia
Tuberculoid
Leonine facies, erythema nodosum leprosum
Lepromatous