Cerebrospinal T-cell responses aid in the diagnosis of tuberculous meningitis in a human immunodeficiency virus- and tuberculosis-endemic population.

RATIONALE: Current tools for the rapid diagnosis of tuberculous meningitis (TBM) are suboptimal. We evaluated the clinical utility of a quantitative RD-1 IFN-gamma T-cell enzyme-linked immunospot (ELISPOT) assay (T-SPOT.TB), using cerebrospinal fluid cells for the rapid immunodiagnosis of TBM. OBJECTIVES: To evaluate the diagnostic utility of the RD1 antigen- specific ELISPOT assay for the diagnosis of tuberculous meningitis. METHODS: The ELISPOT assay was evaluated in 150 patients with suspected TBM who were categorized as definite-TBM, probable-TBM, and non-TBM. Culture or polymerase chain reaction positivity for Mycobacerium tuberculosis served as the reference standard. To determine the diagnostic value of the ELISPOT assay, a clinical prediction rule was derived from baseline clinical and laboratory parameters using a multivariable regression model. MEASUREMENTS AND MAIN RESULTS: A total of 140 patients (81% HIV-infected; median CD4 count, 160 cells/mm(3)) were included in the final analysis. When comparing the definite-TBM (n = 38) and non-TBM groups (n = 48), the ELISPOT assay (cut point of > or =228 spot-forming cells per 1 million mononuclear cells) was a useful rule-in test: sensitivity 58% (95% confidence interval [CI], 41-74); specificity 94% (95% CI, 83-99). However, ELISPOT outcomes improved when other rapid tests were concurrently used to exclude bacterial (Gram stain) and cryptococcal meningitis (latex-agglutination test) within the non-TBM group. Using this approach, the ELISPOT assay (cut point of > or =46 spot-forming cells) was an excellent rule-in test: sensitivity 82% (95% CI, 66-92); specificity 100% (95% CI, 78-100); positive predictive value, 100% (95% CI, 89-100); negative predictive value, 68% (95% CI, 45-86); area under the curve, 0.90. The ELISPOT assay had incremental diagnostic value compared with the clinical prediction rule. CONCLUSIONS: The RD-1 ELISPOT assay, using cerebrospinal fluid mononuclear cells and in conjunction with other rapid confirmatory tests (Gram stain and cryptococcal latex-agglutination test), is an accurate rapid rule-in test for TBM in a TB and HIV endemic setting.

Antibiotic resistance profiles of Campylobacter species in the South Africa private health care sector.

INTRODUCTION: There is a dearth of surveillance data on clinical Campylobacter in South Africa, particularly in the private healthcare environment. We investigated the prevalence of resistance to first-line antibiotics used to treat campylobacterioses in clinical Campylobacter isolates from a private pathology laboratory. METHODOLOGY: Identification of the Campylobacter specific genes were confirmed by PCR. Minimum inhibitory concentrations were determined using the broth micro-dilution method against macrolides (erythromycin, azithromycin), fluoroquinolones (ciprofloxacin, gatifloxacin) and tetracycline. RESULTS: Seventy-two Campylobacter isolates were identified by PCR, with 54 (75%) being classified as C. jejuni and 18 (25%) as C. coli. Of these, 11 (20.4%) C. jejuni and six (33.3%) C. coli strains were resistant to ciprofloxacin and three (7.41%) C. jejuni and three (16.7%) C. coli strains were resistant to gatifloxacin. The number of C. jejuni strains resistant to erythromycin and azithromycin was 17 (31.5%) and 36 (50%) respectively, while the resistance of C. coli strains to erythromycin and azithromycin were seven (38.9%) and 14 (77.8%) respectively. Resistance to tetracycline was detected in 10 (55.6%) C. coli and 14 (25.9%) C. jejuni strains. CONCLUSION: In the light of these resistant profiles, the lack of a South African Campylobacter surveillance program is of concern. Relatively high prevalence of resistance in clinical isolates of C. jejuni and C. coli to the fluoroquinolones, macrolides and tetracycline used in first line treatment is of great concern. The efficacy treating human campylobacteriosis should thus be revisited.

First detection of human dirofilariasis in South Africa.

Humans are occasionally inadvertently infected with dirofilariae, the zoonotic nematodes. We report two cases of human dirofilariasis in South Africa, an area apparently non-endemic for this infection. Dirofilariasis is frequently misdiagnosed, so increased awareness of this entity in areas that are non-endemic is essential for prevention of inappropriate investigations and invasive therapy.