title: Rapid diagnosis of tuberculosis in aspirate, effusions, and cerebrospinal fluid by immunocytochemical detection of Mycobacterium tuberculosis complex specific antigen MPT64.
abstract: The aim of the study was to evaluate the diagnostic potential of immunocytochemical staining for the detection of Mycobacterium tuberculosis complex-specific antigen MPT64, in tuberculous lymph node aspirates, cerebrospinal fluid, and effusions from pleura and abdomen. One hundred ninety patients with a diagnosis of tuberculosis (cases) and 80 patients with nontuberculous lesions (controls) were enrolled and differentiated on the basis of clinical features, histology, cytology, clinical biochemistry, Ziehl-Neelsen staining, Lowenstein-Jensen culture, and response to antituberculous therapy. Cervical lymph nodes fine-needle aspirate (n = 150), cerebrospinal fluid (n = 27), pleural fluid (n = 41), and peritoneal fluid (n = 52) were collected and stained with anti-MPT64 and anti-BCG antibodies using immunocytochemistry. Nested-PCR for IS6110 was done for comparison and to calculate the diagnostic indices of the ICC staining. ICC staining with anti-MPT64 was positive in 128/190 (67.4%) tuberculous smears and in 4/80 (5%) control smears thus giving sensitivity of 67.4% and the specificity of 95%, while anti-BCG was positive in 112 (58.9%) tuberculous smears and in 16/80 (20%) control smears with sensitivity of 58.9% and specificity of 80%. When diagnostic validation of ICC was done using PCR as the gold standard, the overall sensitivity, specificity, positive- and negative-predictive values for ICC staining in smears with anti-MPT64 was 96, 96, 95, and 97%, respectively, while the corresponding values for anti-BCG were 87, 88, 86, and 88%. ICC staining using anti-MPT64 represents a robust and simple method for establishing an early etiological diagnosis of M. tuberculosis complex infection in extrapulmonary tuberculosis.
authors.affiliation: Centre for International Health, University of Bergen, Bergen, Norway.
authors.forename: Manju Raj
authors.initials: MR
authors.lastname: Purohit
authors.forename: Tehmina
authors.initials: T
authors.lastname: Mustafa
authors.forename: Harald G
authors.initials: HG
authors.lastname: Wiker
authors.forename: Lisbet
authors.initials: L
authors.lastname: Sviland
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000942:Antigens, Bacterial / Q000134:cerebrospinal fluid / Q000302:isolation & purification*; D001202:Ascitic Fluid / Q000737:chemistry / Q000382:microbiology; D044963:Biopsy, Fine-Needle; D016022:Case-Control Studies; D002452:Cell Count; D002648:Child; D002675:Child, Preschool; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D008198:Lymph Nodes / Q000737:chemistry / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity; D010996:Pleural Effusion / Q000382:microbiology; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D013194:Staining and Labeling / Q000379:methods; D013997:Time Factors; D014376:Tuberculosis / Q000175:diagnosis* / Q000382:microbiology; D055815:Young Adult
chemical_list: D000942:Antigens, Bacterial; D004269:DNA, Bacterial; C510537:MPT64 protein, Mycobacterium tuberculosis