Transcript Gram Negative Organisms PM2 Pathophysiology

Gram Negative Organisms
PM2 Pathophysiology
Gram Negative Cocci
• Neisseria gonorrheae
• Neisseria meningitidis
Gram negative bacilli
• Escherichia coli
• Salmonella typhi
• Vibrio cholera
• Helicobacter pylori
• Yersinia pestis
• Bordetella pertussis
Neisseria gonorrheae
• MOT: Sexual contact
• Men: acute urethritis
painful urination
yellowish penile discharge
“the drip”
• Women: mostly asymptomatic
more complications:PID, infertility
• Babies: ophthalmia neonatorum
NEISSERIA: DIPLOCOCCI
OPHTHALMIA NEONATORUM
Neisseria meningitidis
• MOT: respiratory droplets
• Causes meningococcemia
disseminated intravascular
coagulopathy
skin rashes  purpura
meningitis
MENINGOCOCCEMIA
Escherichia coli
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MOT: fecal-oral route
Most common cause of UTI
Most common cause of traveller’s diarrhea
Sources: contaminated food and water
Diarrhea:
watery
bloody
• HUS – hemolytic uremic
• syndrome
Salmonella typhi
• MOT: fecal-oral route
• Causes typhoid fever
fever
rose spots
diarrhea
• Carrier state: gallbladder
• Vaccine available
Salmonella typhi
Rose spots
Vibrio cholerae
• MOT: fecal-oral route
• Causes Cholera
profuse, rice-water like diarrhea
hypotension
high mortality of not
treated
Cholera bed
Yersinia pestis
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MOT: bite of rat flea
Causes “the plague”
Common still in Southwest USA
Stages
1. bubonic plague
enlarged, draining lymph nodes; painful,
full of the bacteria
2. pneumonic plague
cough, hemoptysis, highly contagious
3. septicemic plague
CERVICAL BUBOES
INGUINAL BUBOES
SEPTICEMIC PLAGUE
Helicobacter pylori
• MOT: person-to-person
fecal-oral route
• Causes chronic gastritis
• May lead to gastric carcinoma
HELICOBACTER PYLORI
Bordetella pertussis
• MOT: respiratory route
• Causes: whooping cough or pertussis
fever, cough and colds
“whoop”
• Vaccine: DPT vaccine
2, 4 and 6 months of age
booaster at 4 years old
Acid fast bacilli
• Mycobacterium tuberculosis
• Mycobacterium leprae
• Mycobacterium avium-intracellulare
Mycobacterium tuberculosis
• MOT: respiratory droplets
• Causes: pulmonary tuberculosis
miliary tuberculosis
• cough, hemoptysis
• Bones, joints, meninges, kidneys,
peritoneum, lymph nodes, skin, spine
TB
• Abnormal chest x-ray
• PPD test (purified protein derivative test)
• Long treatment: 6 to 9 months
rifampicin
isoniazid
pyrazinamide
ethambutol
• Vaccine: BCG at birth
TUBERCULIN SKIN
TEST/MANTOUX TEST/ PPD
TEST
Mycobacterium leprae
• MOT: contact with nasal secretions or skin
exudates of patients
• Causes: leprosy
• Affects the Schwann cells in the skin;
nerve damage
• Cooler areas affected: eyelids, nose, ears,
scrotum
LEPROSY
Mycobacterium avium-intracellulare
• MOT: respiratory route
• Causes: pulmonary diseases
disseminated disease
• Common in AIDS patients