Rapid Plasma Reagin test (RPR) compared to Venereal Diseases Research Laboratory test (VDRL) for the diagnosis of syphilis in pregnancy.

Obstetric departments which provide service for a large number of patients from different parts of the country and socioeconomic backgrounds like the Obstetric Department of Chulalongkorn hospital, need to develop rapid laboratory tests which can cope with the volume of work and yet provide sound laboratory data for management decisions. We, therefore, undertook a study of the suitable Rapid Plasma Reagin (RPR) test as a diagnostic tool for syphilis in 9,347 pregnant women who attended antenatal clinics at this institute from August 1984 to May 1985. The RPR test was used in addition to the routine serological tests for syphilis namely the VDRL, TPHA and/or FTA-ABS. Analysis of results confirmed that the RPR test fulfilled all laboratory results for clinical requirements. The results from RPR and VDRL were not significantly different. Their sensitivities were 90.86 and 89.95 per cent, their specificities were 99.57 and 99.68 per cent, their positive predictive values were 82.11 and 85.92 per cent, their negative predictive values were 99.8 and 99.78 per cent, and their accuracy was 99.39 and 99.47 per cent respectively. In our study it was found that the RPR test could provide a laboratory diagnosis in 60-90 minutes; in the same morning period when 15-20 prenatal patients were seen for the first time. The above results suggest that the RPR test is a rapid and reliable tool which is particularly suitable for syphilis screening in a busy antenatal clinic. The test enabled all 197 patients with syphilis in pregnancy to be treated promptly and without any loss of follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

Treatment of sexual contacts of syphilitic pregnant women.

Between August 1984 and May 1985, 197 syphilitic pregnant women were diagnosed at the antenatal clinic, Department of Obstetrics & Gynaecology, Faculty of Medicine, Chulalongkorn University. One hundred and sixty-nine male sexual contacts were serologically tested for syphilis and seventy-eight cases were found positive. Twenty-eight cases refused to be tested. Thirty-two syphilitic male contacts had cerebrospinal fluid tests and four were found to be abnormal. Fifty-three cases or 67.9 per cent of 78 syphilitic male consorts did not complete a full diagnostic and treatment protocol. They preferred to be treated with benzathine penicillin G 2.4 million units intramuscularly for 3 consecutive weeks. After this treatment no patient agreed to a repeat spinal tap. This behavioral attitude concurred with their socioeconomic background. All were from a low socioeconomic group and lacked health knowledge. This made it difficult to work with them and contributed to inadequate management of their disease.

Autoantibodies in falciparum malaria: a sequential study in 183 Thai patients.

Various autoantibodies were sequentially studied in 183 consecutive Thai adults infected with Plasmodium falciparum. On the first day of admission, 31.1% of the patients had positive fluorescent anti-nuclear antibodies (FANA) and 16.9% had positive smooth muscle antibodies (SMA). The incidences of positive FANA and SMA rose progressively with times when the patients returned for the 2 and 4 week follow-ups after discharge, although most of their malaria was cured. The majority of the positive FANA and SMA titres lay between 1:20 and 1:160. The positivity of the FANA and SMA did not correlate with the complications of malaria, nor the initial serum IgG or IgA levels. However, they significantly correlated with the initial hyper-IgM. More interestingly, almost all of the positive FANA were of the speckled type of nuclear staining. The antigen specificity of the speckled FANA were found not to be the double stranded DNA or the extractable nuclear antigens. The polyclonal B cell activation in active malarial infection was postulated.

Penicillin concentrations in cerebrospinal fluid after different treatment regimens for syphilis.

The concentrations of penicillin in the cerebrospinal fluid (CSF) were compared simultaneously with those in the serum in 17 patients with syphilis. The antibiotic concentrations were measured by the agar well diffusion method. There were no detectable concentrations of penicillin in the CSF after administration of benzathine penicillin 2.4 megaunits, benzathine penicillin 7.2 megaunits, procaine penicillin in aluminium monostearate (PAM) 12 megaunits, or aqueous procaine penicillin G 2.4 megaunits. Only after high doses of aqueous penicillin G 24 megaunits daily or aqueous penicillin G 2 megaunits daily together with oral probenecid 2 g daily was penicillin detectable in the CSF. The concentrations after the latter regimen were the highest and much higher than the minimum inhibitory concentration for Treponema pallidum.