Chlamydiaceae

Question 1

Characteristics of Chlamydiaceae

Answer 1

Small, gtram negative rods and cocci 
Cell Wall 
- Lacks peptidoglycan 
- High Lipid Content - MNZ positive 
LPS has weak endotoxin activity 
Cannot synthesize ATP 
Obligate Intracellular bacteria 
Unique development cycle

Question 2

Chlamydiaceae Development Cycle

Answer 2

Elementary Bodies 
- Small
- Metabolically inactive 
- Do not Multiply 
- Infectious 
Reticulate Bodies 
- Large 
- Metabolically active 
- Multiply Intracellularly

Question 3

Elementary Bodies

Answer 3

1. Elementary Body attaches to surface of cell
2. Endocytosis of Elementary Body occurs
3. Elementary Body is in endosome which does NOT fuse with lysosome
4. Elementary Body reorganize into reticulate body in endosome
5. RB replicates by binary fission
6. RBs are reorganize to EBs

Question 4

Chlamydiaceae of Transmission

Answer 4

Inhalation and Ingestion of Elementary Bodies

Persistent Carrier State

Question 5

Pathogenesis of Chlamydiaceae

Answer 5

Bacteremia and widespread disseminatin
Replication in vascular endothelium, monocyte, peithelial cells
Latent infection

Question 6

Laboratory Diagnosis of Chlamydiaceae

Answer 6

Direct Examination
Regid cell wall done not have a typical peptidoglycan layer . Therefore B lactam antibiotics are ineffective
Modified Ziehi-Neelson positive
Immunofluorescence
Detection of DNA using PCR
Isolation: Tissue Culture
Serology: ELISA, IFA, Latex agglutination test

Question 7

Chlamydophila felis

Answer 7

Causes: Conjunctivitis (Feline Pneumonitis)

Question 8

Conjunctivitis Feline Pneumonitis

Answer 8

Transmission: Inhalation or contact with ocular discharge
Clinical Findings: Unilateral or bilateral infection, Conjunctivitis, ocular and nasal discharges, irritation of the lining of the respiratory system,
Diagnosis: Examination of conjunctiva scrapings
Immunization: Inactivated and modified live vaccines

Question 9

Bovine Abortion and Infertility

Answer 9

Bacteria: Chlamydophila abortus
Transmission: Ingestion of EBS, veneral transmission from bull to cow
Clinical Findings: Late term abortions, Placentitis, metritis, infertility
Diganosis: Demonstration of inclusions in the epithelial cells of the placenta

Question 10

Enzootic Ovine Abortion

Answer 10

Bacteriology: Chlamydophila abortus
Transmission: Ingestion of EBS and Veneral Transmission have not been reported
Clinical Findings:
- Subclinical intestinal infection which may lead to bacteremia
Placentitis, late term abortion
Reduction is semen quality
Immunization: Inactivated Vaccine

Question 11

Chlamydophila pecorum

Answer 11

Causes: Sporadic Bovine Encephalomyelitis

Question 12

Transmission of Sporadic Bovine Encephalomyelitis

Answer 12

Ingestion of EBs
Subclinical intestinal infection
Vertical transmission to calves through milk

Question 13

Pathogenesis of Chlamydophila pecorum

Answer 13

Systemic infection
Replication in vascular endothelium and serosal epithelia
Serofibrinous pleuritis, peritonitis, pericarditis
Diffuse meningo-encephalitis

Question 14

Clinical Findings of Sporadic Bovine Encephalomyelitis

Answer 14

Most common in young cattle
Fever, excessive salivation, mild diarrhea
CNS signs - stiff gait, circling, paralysis
Diagnosis: Isolation of the organism from the brain
Treatment: Tetracyclines

Question 15

Chlamydophila psittaci

Answer 15

Causes Avian Psittacosis and Ornithosis

Question 16

Avaian Psittacosis and Ornithosis

Answer 16

Penumonia and airsacculitis 
Intestinal infection and diarrhoea 
Conjunctivitis 
Pericarditis 
Encephalitis 
Inhalation and ingestion of EBs 
Replication in the respiratory tract is followed by bacteremia

Question 17

Clinical Findings of Avian Psittacosis and Ornithosis

Answer 17

Characterized by respiratory, disgestive or systemic infection
Poultry - turkeys are more susceptible than chickens
Turkeys - Depression, loose sulfur-colored diarrhea
Parrots - Yellow green diarrheam cerebral hemorrhage
Treatment: Chlortetraycline

Question 18

Human Psittacosis

Answer 18

Bacteria: Chlamydophila psittaci
Inhalation of the dried avian droppings and handling pet birds
Asymptomatic
Septicemia, penumonia, etc