Spontaneous cryptococcal peritonitis in cirrhotic patients.

Spontaneous bacterial peritonitis is a common complication in patients with cirrhosis and ascites. However, spontaneous peritonitis caused by Cryptococcus neoformans is uncommon. Delayed diagnosis of cryptococcal peritonitis often results in death. We describe three cases of spontaneous cryptococcal peritonitis in patients with decompensated cirrhosis. One case had associated symptomatic human immunodeficiency virus infection. Clinical awareness of this entity may lead to the early diagnosis and proper treatment.

In vitro susceptibility testing of levofloxacin and ofloxacin by microtiter plate Alamar blue against multidrug and non multidrug resistant Mycobacterium tuberculosis in Thailand.

Antituberculous drugs for current therapy of multidrugs resistant tuberculosis (MDR-TB) are limited. The in vitro susceptibility of Mycobacterium tuberculosis (MTB) as well as MDR-TB with other antibiotic drugs were determined in order to find alternative drugs for the treatment of MDR-TB. Forty-seven MDR-TB and 62 MTB of clinical isolates were tested against levofloxacin and ofloxacin. The MDR-TB at the MIC90 of levofloxacin and ofloxcain were 1 microg/ml and 2 microg/ml, respectively. Of these MTB, the MIC90 of both drugs were 0.5 microg/ml and 1 microg/ml, respectively. It seemed that levofloxacin MICs of both MDR-TB and MTB were one dilution less than ofloxcin. The promising activity of ofloxacin and levofloxacin against MDR-TB and MTB suggest that both drugs could be used as second-line drugs for MDR-TB or as a good alternative antituberculous drug for patients who have intolerance to the first line drug.

Genotypic subtyping of the HIV-1 polymerase gene in 30 naåve patients from Thailand.

To investigate the subtype classification of the circulating virus strains among infected Thai patients with human immunodeficiency virus type 1 (HIV-1). A random population of patients who were HIV-1 antibody positive after two independent screening assays was selected. HIV RNA from plasma samples was reverse-transcribed and amplified with specific primers that annealed to conserve regions of the HIV-1 pol gene. Amplified products were sequenced directly by using an automated sequencer. The sequencing products represent about 1.2 kb of the pol gene from each patient and they were phylogenetically analyzed and compared to the corresponding pol sequences of the published HIV-1 sequences of known genotypes. Genotype E was found in 25 of 30 patients (83.3%), and 5 patients (16.7%) were HIV-1 genotype B. The result confirmed that HIV-1 subtype E is still predominant in Thailand. Genotype B is found frequently, but there have been no examples of genotype A. In concordance with the serotypic assay, which was previously reported using the V3-peptide enzyme immunoassay (V3-PEIA), the genotypic assay of subtype E was high, at 80% and 83.3% in serotyping and genotyping, respectively. These findings of two subtypes with low heterogeneity indicate that Thailand may be a desirable site for evaluating candidate HIV-1 antiretroviral drugs and vaccines. The mixture of subtype E and B' strains also offers the opportunity to study phenotypic differences between the two subtypes.

Risk factors for penicillin-resistant Streptococcus pneumoniae acquisition in patients in Bangkok.

To identify risk factors for acquisition of penicillin-resistant Streptococcus pneumoniae (PRSP) in patients in Bangkok, using a case-control study, the study included patients with clinical specimens which grew S. pneumoniae during January to December 1997, treated at a teaching hospital in Bangkok. Penicillin susceptibility was determined by E-test and strains with MIC of > 0.1 microg/ml were considered resistant. Cases were the patients who had PRSP, and patients who had penicillin-susceptible S. pneumoniae (PSSP) were controls. The study variables included age 15 years or younger, immunocompromised status, ventilatory support, and antibiotic use or hospitalization within the previous 3 months. There were 73 cases and 51 controls. Their ages were 0 to 87 years, with median age of cases 4 and controls 49 years. Pneumonia was the most common type of infection, being 47% in cases and 45% in controls. Univariate analysis revealed significant association of PRSP acquisition with previous antibiotic use (p<0.0001), age < or = 15 years (p=0.001) and previous hospitalization (p=0.002). Logistic regression analysis in order to adjust for confounding effects showed that the only significant risk factor was previous antibiotic use (OR 18.4; 95% CI 6.2-54.6). The major risk factor for acquisition of PRSP in this study population is recent antibiotic use. Decreased antibiotic use would reduce risk of acquisition of PRSP.

Preliminary report for the application of nucleic acid sequence-based amplification in detection of human cytomegalovirus (HCMV) late pp67 mRNA for diagnosis of HCMV infection.

Human cytomegalovirus (HCMV) late pp67 mRNA expression by nucleic acid sequence-based amplification (NASBA) in patients, clinically diagnosed as possible HCMV, probable HCMV disease, and no disease, was evaluated. The RNAs were isolated from 11 whole-blood samples of 11 patients for the specific amplification of the pp67 mRNA. NASBA results were compared to results from PCR assay and serological assay. The HCMV pp67 mRNA could be found in 3 of 11 patients, whereas, HCMV-DNA PCR was positive in 6 of 11 patients. PCR assay for HCMV-DNA in plasma has proved to correlate with clinical diagnosis of HCMV infection. Only 2 patient samples of NASBA positive results coincided with HCMV-DNA PCR. However, the diagnosis of clinically relevant HCMV infection by NASBA was seen. Anti-CMV IgG titers of 1:1,600 or over 1:1,600 were found in 2 of 3 NASBA positive cases and 5 of 6 HCMV-DNA positive cases, whereas, anti-CMV IgM were all negative. These results showed the correlation of HCMV infection detected by NASBA, PCR assay and anti-CMV IgG of the titers up to 1:1,600. Additionally, a low antibody titer of the HIV patient could be diagnosed by NASBA or PCR. In conclusion, pp67 mRNA NASBA appears to be a promising diagnostic tool in analysis of HCMV infection and/or disease. Its diagnostic value should be defined in the specific group for the follow-up of immunocompromised patients, such as organ transplant recipients in future prospective studies.

Pharmacokinetics of levofloxacin in healthy Thai male volunteers.

The pharmacokinetics of levofloxacin, a new fluoroquinolone, were investigated in 12 healthy Thai male volunteers with an average age (SD) of 22.92 (2.50) years. A single oral dose of 300 mg or 500 mg levofloxacin was given to subjects following an 8- hour overnight fast. The drug was given in a controlled, randomized, 2 x 2 crossover design with a 1 week washout period. Venous blood samples were drawn prior to and from 0.25 up to 48 hours after dosing. Plasma levofloxacin concentrations were determined by HPLC assay. The pharmacokinetics of levofloxacin were well described by a linear, 2-compartment open model with first-order absorption with lag time and first-order elimination. Mean +/- SEM of Cmax after 300 mg and 500 mg dose was 4.83 +/- 0.33 and 7.75 +/- 0.71 micrograms/mL, respectively. Tmax ranged from 0.7 to 0.8 hours for both doses. Mean +/- SEM of AUC0-infinity was 35.77 +/- 2.06 micrograms x h/mL for 300 mg dose and 61.57 +/- 2.84 micrograms x h/mL for 500 mg dose. High distribution with VSS/F value of approximately 1.5 L/kg was demonstrated after both doses. Mean +/- SEM of CL/F value was 8.64 +/- 0.41 L/h and 8.31 +/- 0.37 L/h for a 300-mg and a 500-mg dose, respectively. Long t1/2 beta of 7 to 8 hours with the mean residence time of 10.43 +/- 0.43 hours and 10.49 +/- 0.38 hours after 300 mg and 500 mg dose, respectively, was observed. The results suggested that an oral 300 mg dose once daily provides sufficient Cmax to cover most Gram-negative and atypical bacteria (median MIC90 0.032-0.5 microgram/mL) common in mild to moderate respiratory tract infections or complicated urinary tract infections and Gram-positive bacteria (median MIC90 0.5 microgram/mL) common in skin and soft tissue infections. For severe cases or Streptococcus pneumoniae (MIC90 2 micrograms/mL) infection, a 500-mg dose should be recommended.