B.vincenti Normal mouth commensal May give rise to ulcerative gingivostomatitis or oropharyngitis (Vincent’s angina) during malnutrition or viral infections B. vincenti always associated with fusiform bacilli – fusospirochetosis Diagnosis – gram staining of exudates Treatment – Penicillin
7 Diagnosis serum antibodies to B. burgdorferi serum antibodies to B. burgdorferi. laboratory strains – grow extremely slowly – tissue culture media – not bacteriological media patient body fluids/tissue sample patient body fluids/tissue sample – almost never growth
8 acute – responds to antibiotic –antibodies not detectable late diagnosis late diagnosis – not curable – antibodies detectable A physicians dilemma
9 Lyme Disease - etiology reactive arthritis similar to reactive arthritis similar to – Reiter's syndrome – rheumatic fever resembles rheumatoid arthritis.
Leptospira Very thin, delicate spirochetes with hooked ends 2 species are recognised : 1.L. interrogans – include human pathogenic serogroups: L.icterohaemorrhagiae (rats are the reservoir) 2.L. biflexa – saprophytic, mainly found in surface water.
Laboratory characteristics Morphology – stained with Giemsa/ silver impregnation, hooked ends resemble umbrella handles Culture – media (semi solid/ liquid) enriched with rabbit serum - Fletcher’s medium Pathogenicity – causes Weil’ disease (leptospirosis)
Weil’s disease Transmission - Leptospires in water contaminated by the urine of rats; enters the body through cuts or abrasions on the skin or through intact mucosa of mouth, nose or conjunctiva Incubation period – about 10 days (2 to 26) Mild fever to severe or fatal illness with hepatorenal damage Fever, rigors, headache, vomiting, icterus, purpuric hemorrhages
Diagnosis Examination of blood – 1 st week only Urine – 2 nd week of disease, should be examined immediately after voiding Serology – Abs appear by the end of 1 st week & increase till 4 th week of disease. Treatment Should be started early in disease Penicillin I.V., Tetracyclines