Fine needle aspiration of the thyroid gland.

Fine needle aspiration (FNA) has become a major diagnostic triage for clinical management of patients with a thyroid mass. Diagnostic accuracy of this procedure can be evaluated by cyto-histologic correlation. Out of 1,761 fine needle aspirates of thyroid glands performed from January 1996 to December 1999, 230 satisfactory specimens contained respective histologic correlates. Using histologic diagnoses as the gold standard, the overall accuracy, sensitivity and specificity for cytologic diagnoses of thyroid neoplasm were 90.4 per cent, 85.7 per cent, and 92.5 per cent respectively. The positive predictive value for diagnosing thyroid neoplasm was 83.3 per cent while the negative predictive value was 93.7 per cent. The common pairs of cyto-histological diagnostic discrepancy included adenomatous goiter vs follicular neoplasm, adenomatous goiter vs papillary carcinoma, and thyroiditis vs follicular neoplasm. In conclusion, FNA is a rapid, reliable and safe diagnostic tool to distinguish non-neoplastic from neoplastic lesions in patients with thyroid masses.

Use of PCR-PIRA for screening of a point mutation at codon 12 in K-ras oncogene obtained from paraffin embedded tissue sections.

Among various methods which have been developed for facilitating the screening of point mutations in human genomic DNA, PCR-Primer Introduced Restriction Analysis (PCR-PIRA) is of particular interest due to its practicality and short procedure allowing detection of point mutations by simple restriction enzyme digestion directly after PCR amplification. However, one limitation of PCR-PIRA method is the absence of restriction sites in the region of detection, thus creation of the recognition site in primers has been introduced. Detection of a point mutation at codon 12 in K-ras oncogene by BstNI requires one base change in the primer sequence so that only the normal but not mutant PCR product will be digested by the enzyme. However, false positive results generated from undigested normal DNA sequence are always obtained. This effect is compounded when it is used to analyse mixed cell populations in paraffin embedded section of cancer cells. Assay of a mutant band generated from normal DNA by densitometric quantitation enabled the determination of background values and thereby eliminated false positive results. Samples with higher ratios between mutant and normal bands than the background one after the first PCR-PIRA would be subjected to the second PCR-PIRA in order to confirm the results. Screening of such mutations in cervical carcinomas from paraffin embedded sections using the above criteria should reduce misinterpretation of PCR-PIRA results.

Histopathologic spectrum of AIDS-associated lesions in Maharaj Nakorn Chiang Mai Hospital.

The histopathological alterations in various organs and the presence of AIDS-associated lesions were studied in 86 biopsy and 29 necropsy specimens of AIDS patients. The most common cancer seen in this study were malignant lymphomas (4% of cases) with development of extensive extranodal lymphomatous involvement from the outset. Although a preponderance of high grade B-cell pathologic subtypes is found in AIDS-associated lymphoma, we also report the first case of T-lymphoblastic lymphoma with a picture of acute lymphoblastic leukemia (T-ALL). Tuberculosis (34% of cases) was the most common opportunistic infection presented in tissue sections, and the majority of tissue biopsies revealed poorly organized granulomas and extensive necrosis with numerous bacilli. Penicilliosis (20% of cases) appeared to be the most common cutaneous lesion with multiple organ involvement. The involved organs showed a partially anergic tissue reaction characterized by poorly formed granulomas with diffuse infiltrate of fungi-laden macrophages and lymphoid cell depletion. This organism has to be distinguished from Histoplasma capsulatum and other yeast-form fungi. Co-existing cytomegalovirus and P. carinii infections were the predominant findings in lung necropsy specimens from pediatric patients who died from AIDS. A major pathologic feature in this group was diffuse alveolar damage stage II to III with heavy loads of organism and extensive lymphoplasmacytic infiltration.

Detection of various types of human papillomaviruses in premalignant and malignant cervical lesions using DNA-DNA in situ hybridization.

Detection of human papillomavirus (HPV) in formalin-fixed paraffin embedded tissue sections by in situ hybridization technique employing biotinylated (HPV) DNA probe 6/11, 16/18 and 31/33/35 was done retrospectively in 25 cases of cervical dysplasia, 32 cases of cervical squamous cell carcinoma in situ, 52 cases of invasive cervical squamous cell carcinoma and 7 cases of adenocarcinoma. HPV could be demonstrated in 10 cases (40.00%) of cervical dysplasia, 8 cases (25.00%) of cervical squamous cell carcinoma in situ and 31 cases (59.61%) of invasive cervical squamous cell carcinoma and 4 cases (57.14%) of adenocarcinoma. Among the dysplastic cases, 4 cases showed HPV 31/33/35, 4 cases showed HPV 16/18 together with HPV 31/33/35, 1 case showed mixed typing of HPV 6/11 and 31/33/35, and 1 case showed mixed typing of HPV 6/11, 16/18 and 31/33/35. In 32 cases of squamous cell carcinoma in situ, 1 case of HPV 6/11; 3 cases of HPV 16/18, 3 cases of HPV 31/33/35 and 1 case of mixed typing of HPV 16/18 and 31/33/35 were present. A case of HPV 6/11, 10 cases of HPV 16/18 and 9 cases of HPV 31/33/35 could be detected among the cases of invasive squamous cell carcinoma. Mixed typing of HPV 6/11 and 16/18; HPV 6/11 and 31/33/35; HPV 16/18 and 31/33/35; HPV 6/11, 16/18 and 31/33/35 were revealed in 2, 1, 3 and 5 cases of invasive squamous cell carcinoma, respectively. In 7 cases of adenocarcinoma, 1, 2 and 1 cases exhibited positivity for HPV 16/18; HPV 6/11 and HPV 16/18; and HPV 16/18 and HPV 31/33/35.(ABSTRACT TRUNCATED AT 250 WORDS)

Disseminated cutaneous cytomegalic inclusion disease resembling prurigo nodularis in a HIV-infected patient: a case report and literature review.

Cytomegalovirus infection is common disease but most of the healthy patients are asymptomatic. Cytomegalovirus infection is a serious problem in immunocompromised patients particularly in acquired immunodeficiency syndrome. About 90 per cent of patients with AIDS develop active cytomegalovirus infection and up to 25 per cent may experience life threatening infection due to the virus. However, cytomegalovirus cutaneous lesion have rarely been reported. A 40-year-old Thai man presented with multiple prurigo nodularis-like lesions on both legs and feet. The investigation revealed consistent with acquired immunodeficiency syndrome associated with cytomegalovirus cutaneous infection.

Immunohistochemical analysis of non-Hodgkin's lymphomas with the monoclonal antibody to follicular center lymphocytes reactive in paraffin sections.

The monoclonal antibody designated LN-1 was used in an attempt to identify the antigen in follicular center cell lymphomas using tissue sections fixed in formalin. The LN-1 antibody has been shown in previous studies to identify follicular center cells and give reproducible results in tissue fixed in B5. We used the ABC peroxidase technique to examined formalin-fixed, paraffin embedded sections representing 52 cases of various histologic subgroups of non-Hodgkin's lymphomas based upon the Lukes-Collins classification. Following immunostaining with LN-1 using overnight incubation of the antibody and papain treated sections, 37 cases, and all of the 38 cases previously diagnosed as follicular center cell lymphomas, gave a positive reaction to the LN-1 monoclonal antibody.

Salmonella aortitis at Ramathibodi Hospital, Bangkok, Thailand.

Two cases of Salmonella aortitis were diagnosed by positive culture from the wall of aortic aneurysm. Common features in both cases included fever, abdominal/back pain and pulsatile abdominal mass with underlying severe atherosclerosis. The fatal outcome of both cases despite surgical and medical treatment was discussed and guideline of management was proposed.