Comparison of a combined nontreponemal (VDRL) and treponemal immunoblot to traditional nontreponemal and treponemal assays.

BACKGROUND: Serology is the mainstay for the diagnosis and management of patients with syphilis. Newer technologies such as immunoblotting are now available for the diagnosis of syphilis. METHODS: A commercial IgM/IgG immunoblot assay that detects both nontreponemal (VDRL-Venereal Disease Research Laboratory) and treponemal antibodies was compared with standard nontreponemal and treponemal assays. The immunoblot and T. pallidum particle agglutination assay (TP-PA) were performed on 198 samples. Ninety-seven samples were Rapid plasma reagin (RPR)-positive and one hundred one were RPR-negative. Positive RPR samples were titered by VDRL. RESULTS: The agreement, sensitivity, and specificity of the IgM/IgG VDRL results of the immunoblot compared to RPR were 74.2% (95% CI: 67.2-80.2), 77.3% (95% CI: 70.2-83.4), and 71.3% (95% CI: 64.4-77.1), respectively. The agreement, sensitivity, and specificity of the IgM/IgG treponemal immunoblot compared to TP-PA were 100% for all parameters, if the ten equivocal results were not used in the calculation. CONCLUSION: The treponemal portion of the ViraBlot IgM/IgG immunoblot compared well with the treponemal confirmation assay and could be a useful supplemental method to fluorescent treponemal antibody or TP-PA for the confirmation of syphilis. The addition of the detection of nontreponemal antibodies to the immunoblot assay, however, may not be of added benefit to the overall assay, due to decreased sensitivity and specificity compared to standard assays.

Complete resolution of advanced Mycoplasma pneumoniae encephalitis mimicking brain mass lesions: report of two pediatric cases and review of literature.

Mycoplasma pneumoniae is a well-known cause of atypical pneumonia. CNS involvement is a relatively frequent extrapulmonary manifestation, most commonly manifesting as encephalitis in the pediatric population. We present two unusual cases of M. pneumoniae encephalitis that presented with symptoms and imaging findings suggesting mass occupying lesions, and worsening altered mental status. Biopsy of the lesions was necessary in both cases to aid with diagnosis. Histopathologic features excluded neoplasm, and established the diagnosis of encephalitis, but did not point toward its etiology. The only finding that indicated M. pneumoniae as the most likely pathogen was serum IgM positivity in the absence of any other identifiable infectious source, and complete neurologic recovery following specific anti-mycoplasmal treatment. The patients were successfully treated with antibiotics and steroids, with the second case also requiring intravenous immunoglobulin and anti-epileptics. The clinical presentation and histopathologic findings suggested an immune-mediated pathogenesis, but acute disseminated encephalomyelitis was excluded due to extensive gray matter involvement. Disease resolution despite status epilepticus and herniation in case 2 is a novel finding of the study. Current principles of diagnosis and management of encephalitis as the presenting manifestation of mycoplasmal infection are discussed.

Restoring point-of-care testing during parathyroidectomy with a newer parathyroid hormone assay.

OBJECTIVE: Intraoperative parathyroid hormone (IOPTH) monitoring has emerged as a useful adjunct in parathyroidectomy. Originally performed within the operating room, removal of the Nichols assay from the market forced many surgeons to rely on testing done in central laboratories, reducing convenience and prolonging operative times. The authors hypothesized that PTH assessment with a newer point-of-care (POC) assay would reduce results reporting time compared with central-laboratory PTH assays. STUDY DESIGN: Cross-sectional study with planned data collection. SETTING: Academic medical center. SUBJECTS AND METHODS: Patients underwent parathyroidectomy for primary or recurrent hyperparathyroidism. Intraoperative monitoring of serum PTH levels was used to confirm biochemical cure following adenoma excision. Samples were run in duplicate using both a POC PTH assay (Future Diagnostics) located within the operating room and a laboratory-based assay (Turbo PTH). Samples were taken at incision and at 5-, 10-, and 15-minute intervals following removal of suspected parathyroid adenomas. Results reporting time was recorded and compared by nonparametric Wilcoxon rank sum test. RESULTS: Sixty-six serum samples were assayed. There was excellent correlation between POC and central-laboratory IOPTH results (r = 0.880, P < .001). The POC IOPTH results were available faster than corresponding central-laboratory results, with a mean of 14.4 minutes compared with 30.7 minutes, respectively (P < .001). All patients (100%) demonstrated a biochemical cure by the end of the procedure. CONCLUSION: Use of a rapid POC IOPTH assay results in a significant decrease in the amount of time for laboratory results to be communicated to the surgical team. This reduces operative times for parathyroidectomy and improves patient care.