Micro Exam 3 Data

Name the characteristics of Clostridium. Name the three major categories of Clostridium, and the four C. diseases. name their effects in humans and animals if they differ. Name the toxins that they each produce, and their major effect. Describe what damages Clostridium and why.

Gram +ve, spore +ve, anaerobe

Neurotoxic:

• c. botulinum - botulism, blocks AcOA (keeps muscles relaxed), constipation

• c. tetani - tetanus, exotoxin tetanospasm AB, lockjaw/respiratory failure

Histotoxic:

• c. perfringens - Enteritis/septicemia (humans), myonecrosis/gas gangrene (animals), histotoxin, soil

Enteric

• c. difficile - pseudomembranous colitis, enteritis, TcdA (enterotoxin) + TcdB (cytotoxin), tx: vancomycin, metronidazole

enterotoxin: heat-stable, cause food poisoning sx, disrupt stomach mucosal cells

cytotoxin: toxic to cells, trigger inflammation

damaged by O2 (lack enzymes to detoxify radicals, ex: peroxidases, catalase)

Name the characteristics of Neisseria. name the two pathogenic species. name the treatment. Name the VF of gonorrhoeae.

Gram -ve, spore -ve, diplococci, nonmotile, pyogenic

• n. meningitidis - external polysaccharide capsule, B = USA, A = developing countries

• n. gonorrhoeae: STI, to desiccation, colonize epithelium

  • VF: Pili, PorB, Opa

LOS instead of LPS (no O-antigen)

Tx: penicillin, rifampin + cipro

Pili + Opa = adhesion

Describe the cell wall and morphological forms of Chlamydia. Name the three pathogenic strains of Chlamydia and their symptoms. Which strain of c. is associated with poultry processesing?

Grow in vacuoles. reticulate body (rest n digest) vs elementary body (extracellular, transmissable, strong)

• c. trachomatis: trachoma, A-C neonate conjunctivitis, cervicitis D-K

• c. psittaci - pneumonia, poultry

• c. pneumoniae - pneumonia, RTIs

Describe the cell wall of mycoplasma. Describe the nature of most mycoplasma. Describe the four pathogenic strains.

No cell wall, sterol cell membrane. Facultative anaerobes. do not replicate in environment (enriched media required). pleomorphic.

• M. pneumoniae - ‘walking pneumonia’, patchy x-ray

• m. hominia + m. urealyticum - GUIs

• m. mycoides - contagious bovine pleuropneumonia

• m. hyopneumoniae - enzootic pig pneumonia

Describe the nature of Spirochetes, plus what makes the filaments special. Describe the four pathogenic strains of Treponema. Describe how to image T.P, and it’s VFs. Describe syphilis and the four stages. Describe the treatment for most TP strains.

gram -ve, corkscrew, axial filaments, motile

must be imaged in dark-field or fluorescent

VF: OMP (adherence), HAse, fibronectin (stops phagocytocis)

• TP pallidum - syphilis

• TP endemicum - bejel, endemic syphilis

• TP carateum - pinta (skin)

• TP pertenue - yaws (benign lumps)

tx: penicillin

syphilis:

1’ chancre

2’ rash + meningitis/hepatitis

3’ gumma, CNS

latent asymptomatic

Name the agent that causes Lyme disease, and its shape. Name the vector, host, and reservoir. Name the two fevers, and the three stages.

Borrealia, spirochetes

vector: black-legged tick

reservoir: mice/rodents

• epidemic relapsing fever

• endemic relapsing fever

1’ erythema migrans (bullseye rash), flu-sx

2’ arthralgia, cardiac/neurologic

3’ chronic arthritis + CNS

name the three spirochetes described in this course

Borrelia (lyme disease), Treponema pallidum (syphilis), leptospira

Describe the nature of leptospira, its method of transmission, its nature of growth in culture, aliases, and symptoms.

Spirochetes, hook-ends

transmission: contaminated water (urine from rodents/livestock)

slow growth in culture

‘marsh fever’, ‘Weil disease’, ‘swineherd’s disease’

Sx: jaundice, hemorrhage, necrosis, red eyes, aseptic meningitis

Describe the basic nature of mycobacterium and it’s cell wall. What type of staining would you use? How does it grow on medium and what medium? Describe the two pathogenic strains and the stages of TB.

rods, nonmotile, spore -ve, lipid (mycolic acid) cell wall = acid fast staining, slow growth on Lowenstein-Jensen agar, aerobic

• M. tuberculosis

1’ initial, mild, children, alveolar macrophages

2’ reactivation, opportunistic, adults, caseous granulomas

miliary: bacteria enter bloodstream and disseminate

• M. leprae: live medium (armdillos), skin lesions, nerve damage

gram staining doesn’t work because the waxy fatty cell wall creates a hydrophobic barrier

Describe the host of the plague, the vector, and the two types. Describe the two cycles

host: rodents

vector: infected fleas

• bubonic plague - zoonotic, buboes, can cause pneumonic (bacteremia)

• pneumonic plague - humans

sylvatic and urban cycle

Describe the cause, vector, and nature of tuleremia.

francisella tularensis: gram -ve cocci, non-motile, aerobes, ox-, cat+, intracellular, long survive in environment

vector: tick bites, direct contact

‘rabbit fever’

long-lasting immunity after natural infection

describe the nature of Rickettsiaceae, and the 7 pathogenic strains (and their vector and clinical sx)

gram -ve coccobacilli, intracellular

• R. rickettsii - RMSF, ticks, inward macular rash

• Epidemic typhus - lice, outward macular rash

• endemic typhus - fleas, gradual, maculopapular rash

• Rickettsialpox - mites, abrupt, papulovesicular rash + sloughing

• q fever - no vector

• Ehrlichiosis - hepatitis, ticks

• cat-scratch fever - cat fleas, lice, initial pustule + benign regional lymphadenopathy

Describe how Brucellosis is transmitted, and its symptoms

Via contact with infected animals, unpasteurized dairy products, undercooked meat

sx: 1-6 weeks, fever, joint pain, weight loss

Describe the three types of fungal diseases, and the two ways they cause disease

Cutaneous, subcutaneous, systemic

allergy - mycotoxins (ex: aflatoxin), toxin-mediated hypersensitivity (Type II cytotoxic)

infection - mycoses

Describe the nature of histoplasmosis

‘Ohio Valley Fever’ = nitrogen rich moist soil, Eastern/Central US, dimorphic

• inhaled conidia cause pulmonary infection

tx: amphotericin B, ketoconazole

name the fungal infections described in this course

Histoplasmosis, coccidioidomycosis, mucormycosis, aspergillosis, candidiasis

Describe coccidioidomycosis

‘Valley Fever’, spores enter lungs, germinate, develop spherules with endospores

• Disseminates and creates bone and CNS lesions

Describe mucormycosis

mucormycetes (rare), opportunistic, lungs + sinuses

Describe aspergillosis

healthy individuals - allergic sinusitis, allergic bronchopulmonary aspergillosis

immunocompromised - chronic pulmonary aspergillosis, invasive aspergillosis (high mortality)