This document discusses laboratory diagnosis of Lymphogranuloma venereum (LVG). It outlines various diagnostic modalities including microscopy, direct immunofluorescence, culture, serology, and nucleic acid amplification tests. Microscopy has low sensitivity for detecting Chlamydia. Culture was previously the gold standard but NAAT is now considered the most sensitive and specific method as it can detect DNA copies and is less time consuming. Serology tests for antibodies and NAAT targets rRNA genes. Treatment recommended by CDC and NACO involves a 21 day course of doxycycline.

1. LYMPHOGRANULOMA
VENEREUM

2. LABORATORY DIAGNOSIS:
• Specimen required are:
Serum
scraping from ulcer base
lymph node aspirate

3. DIAGNOSTIC MODALITIES:
1. Microscopy
2. Direct immunofluorescence
3. Culture
4. Serology
5. Nucleic acid amplification tests(NAAT)

4. MICROSCOPY:
• Chlamydia are gram negative but they are poorly stained
• Hence microscopy is not recommended
• When stained with lugols iodine MIYAGAWA CORPUSCLE are
seen

5. DIRECT IMMUNOFLUORESCENCE:
• Swabs are rolled on to a taflon coated slide
• fixed in methanol
• Fluorescent tagged monoclonal antibody
• DIF is sensitive but specificity is poor

6. CULTURE:
• Previously considered as gold standard method
• Highly specific but less sensitive
• Time consuming
• Technically demanding
• CHOICE OF CELL LINE:
• McCoy, HeLa 229, BHK-21

7. SEROLOGY:
• Complement fixation test (>1:64) using LPS antigen
• ELISA- using LPS antigen
• Microimmunofluorescence(>1:512) using MOMP antigen

8. OTHER TESTS:
• FREI TEST:
• Previously used
• Demonstrate type 4 hypersensitivity reaction
• ID skin test

9. NAAT:
• Considered as gold standard method
• Highly sensitive and specific
• Less time consuming
• Can detect even few copies of DNA
• GENES TARGETED: 16S OR 23S rRNA

10. TREATMENT (CDC)
• Recommended Regimen
Doxycycline 100 mg orally BD for 21 days

11. TREATMENT (NACO)