Mycoplasma hominis septic arthritis with concomitant gouty arthritis.

We report a rare case of Mycoplasma hominis septic arthritis occurring simultaneously with acute gout. A Taiwanese native aboriginal presented with right ankle swelling, erythema, local tenderness, and limitation of range of motion after a vertebroplasty. He had a history of gout without regular follow-up. Under the polarized light microscopy examination, his synovial fluid revealed neutrophilic leukocytosis and monosodium urate crystals. Subsequently, 2 consecutive anaerobic synovial fluid cultures yielded a cell wall-free microorganism, which was identified as M. hominis based on polymerase chain reaction of its 16S rDNA. He did not defervesce under colchicine and indomethacin treatment until we prescribed a doxycycline and moxifloxacin regimen. He responded well to 6-week doxycycline and moxifloxacin treatment without bone destruction and loss of joint function.

Use of X-linked short tandem repeats loci to confirm mutations in parentage caseworks.

BACKGROUND: Analysis of short tandem repeats (STRs) has become wide-spread in routine for parentage test. However, the accuracy of STR is sometimes interfered by the presence of microsatellite mutations. Analysis of other DNA markers such as the HV1 and HV2 hypervariable regions of mitochondrial DNA or the Y-STR becomes essential to settle the noncongruence. Owing to the time-consuming nature of these tests, we explored here the use of X-chromosome STR (X-STR) to resolve the paternity and maternity disputes. METHODS: At first, the autosomal STR mutation frequencies among 4758 Taiwanese were analyzed. Population data were obtained from randomly selected 99 females and 101 males to setup the X-STR database. Two families with a mismatch of one allele in autosomal STR analysis were subjected to the X-STR test to explore its clinical application. RESULTS: The STR mutations occurred in all 15 autosomal STR loci with the exception of TH01 and TPOX. The mutation rates could reach as high as 0.106% for the loci of D8S1179 and D18S51. As to the X-STR frequencies, the probability values of exact tests for Hardy-Weinberg equilibrium were 0.1471, 0.0019, 0.0025, 0.1427, and 0.1167 for the loci of DXS7132, DXS981, DXS6789, DXS101, and HPRTB, respectively. In addition, 33 and 34 different haplotypes were revealed for DXS101-DXS6789 and DXS7132-DXS981, respectively. Furthermore, two cases with one allele mismatch in routine parentage test were resolved by performing X-STR analysis. CONCLUSION: Typing of X-STR markers is recommended for parentage test when 1 or 2 alleles mismatch is present or when the samples are difficult to be analyzed.

Lack of STK11 gene expression in homozygous twins with Peutz-Jeghers syndrome.

Clinical features of Peutz-Jeghers syndrome (PJS), an autosomal dominant disorder, include clusters of melanotic spots on the lips and limbs, polyposis of the gastrointestinal (GI) tract, and propensity to develop neoplasms of the GI tract, ovaries, testes, and other sites. We report twin sisters with PJS who were found to be homozygous, based on analyses of 9 DNA markers containing short tandem repeats (STR). Aberrant expression of a putative tumor suppressor gene, STK11, which encodes a serine threonine kinase, has been suggested as the etiologic factor in PJS. In both of the twin sisters with PJS, mRNA analyses by RT-PCR demonstrated a complete lack of STK11 gene expression. These results provide direct evidence that STK11 gene expression is abnormal in PJS. Detecting abnormal expression of the STK11 gene may serve as a molecular approach to the diagnosis of PJS and may facilitate genotype-phenotype correlations in PJS patients.

Polymerase chain reaction used for the detection of airborne Mycobacterium tuberculosis in health care settings.

BACKGROUND: Tuberculosis (TB) has re-emerged as a major infectious disease in several areas in the world. Airborne tubercle bacilli produced by individuals with pulmonary TB and droplet nuclei remain suspended in the air for a long time. This study attempts to use a sensitive polymerase chain reaction (PCR) analytic method coupled with a filter sampling method to detect the presence of airborne Mycobacterium tuberculosis (MTb) in health care settings. METHODS: Patients with TB history were recruited from a medical intensive care department and negative-pressure isolation rooms at Chang Gung Memorial Hospital in Taichung City, Taiwan, Republic of China. The exhaled gas from different patients with TB who were mechanically ventilated in the intensive care department was collected using a polycarbonate (PC) membrane or polytetrafluoroethylene (PTFE) filter. Airborne MTb concentrations in air exhausted through a bacterial filter attached to a mechanic ventilator were studied. Indoor air samples were taken through a 3-piece cassette with a filter (PC/PTFE) in patient rooms. MTb concentrations in these filters were analyzed using the PCR method. RESULTS: Overall, 75% (12/16) of the exhaled-gas samples in PTFE filters and 25% (4/16) of samples in PC filters were detected as having positive MTb-specific DNA products. Exhausted air from the bacterial filters in mechanic ventilators was found to have positive PCR results (57% in PC filters and 14% in PTFE filters) for MTb. Both negative-pressure isolation rooms and outpatient department areas in the TB center had positive samples (40%-60% in PC/PTFE filters) containing MTb by PCR amplification. CONCLUSIONS: Health care settings were sufficient for various risk factors, including physical, chemical, and biologic hazards. Infectious agents are produced by aerosolization that results in human respiratory-related diseases. The indoor air quality of the entire hospital environment should, therefore, be monitored by health care personnel and the public.

STR data for the AmpFlSTR SGM Plus and Profiler loci from Taiwan.

Allele frequencies for the 15 STRs included in the AmpFlSTR SGM Plus and Profiler kit (D3S1358, VWA, D16S539, D2S1338, D8S1179, D21S11, D18S51, D19S433, THO1, FGA, TPOX, CSF1PO, D5S818, D13S317 and D7S820) were obtained from a sample of 597 unrelated individuals living in Taiwan. All loci, except for D8S1179 and D5S818, are in Hardy-Weinberg equilibrium.

Detection of Sporothrix schenckii in clinical samples by a nested PCR assay.

Cutaneous sporotrichosis is a chronic granulomatous fungal infection caused by Sporothrix schenckii with worldwide distribution. Its traditional diagnosis is time-consuming and difficult to differentiate from that of a clinical sporotrichoid lesion caused by various pathogens. In this study, a nested PCR assay for the detection of S. schenckii was evaluated by using a sequence of 18S rRNA gene as a target. For the examination of specificity and sensitivity, five clinical isolates with 1 ATCC 10213 strain of S. schenckii, 10 strains of clinical common fungi, 3 strains of Mycobacterium spp., Staphylococcus aureus, and normal human skin tissue were used. The expected fragment was amplified from six S. schenckii isolates in the first round and nested PCR but not from other microorganisms and human DNA. Their sequences were 100% identical to the S. schenckii 18S rRNA gene sequence deposited in GenBank. A detection limit of 40 fg of S. schenckii DNA extract was determined with ethidium bromide staining. Serial dilution studies demonstrated that the nested PCR could detect a DNA amount of 1 CFU of S. schenckii in tissue samples. We further investigated the nested PCR assay for the detection of S. schenckii from the tail tissues of 5 experimentally infected mice and from the clinical biopsy specimens of 12 patients with sporotrichosis confirmed by culture or histochemical staining. The nested PCR assay was positive in all 5 infected mice and in 11 of the 12 clinical specimens. The high sensitivity and specificity of this nested PCR indicate that the assay can provide rapid diagnosis with sufficient accuracy to be clinically useful for patients with sporotrichosis.