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Masoom Kassi

Publications and source records attributed to Masoom Kassi.

3 recordsLinked to original sources
PubMed2005

Quantitative nucleic acid sequence-based assay as a new molecular tool for detection and quantification of Leishmania parasites in skin biopsy samples.

Currently available methods for the diagnosis of cutaneous leishmaniasis (CL) have low sensitivities or are unable to quantify the number of viable parasites. This constitutes a major obstacle for the diagnosis of the disease and for the study of the effectiveness of treatment schedules and urges the development of improved detection methods. In this study, quantitative nucleic acid sequence-based amplification (QT-NASBA) technology was used to detect and quantify Leishmania parasites in skin biopsy samples from CL patients. The assay is based on the detection of a small subunit rRNA (18S rRNA), which may allow for the detection of viable parasites. The QT-NASBA assay was evaluated using in vitro-cultured promastigotes and amastigotes and 2-mm skin biopsy samples from Old and New World CL patients. The study demonstrated that the lower detection limit of the QT-NASBA was two parasites per biopsy sample. Parasites could be quantified in a range of 2 to 11,300,000 parasites per biopsy sample. The QT-NASBA could detect levels of parasites 100-fold lower than those detected by conventional PCR. Test evaluation revealed that the QT-NASBA had a sensitivity of 97.5% and a specificity of 100% in the present study. The QT-NASBA is a highly sensitive and specific method that allows quantification of both Old and New World Leishmania parasites in skin biopsy samples and may provide an important tool for diagnosis as well as for monitoring the therapy of CL patients.

Adolescent↗
PubMedDate not supplied

Fine-needle aspiration cytology in the diagnosis of cutaneous leishmaniasis.

BACKGROUND: In areas of endemicity without sufficient laboratory infrastructure, cutaneous leishmaniasis (CL) is often diagnosed on the basis of clinical characteristics, but parasitologic confirmation is essential to exclude erroneous diagnoses. We compared fine-needle aspiration cytology (FNAC) with the conventional method of excisional biopsy to assess the efficacy, utility and accuracy of FNAC for the diagnosis of CL. MATERIALS AND METHODS: In a consecutive series of 100 patients referred for a suspected CL lesion during June 2001 to May 2002, FNAC and 'excisional biopsy followed by histopathology' were done using hematoxylin and eosin (H&E) stain for both procedures. RESULTS: The study group included 40 males and 60 females, ranging in age from 1 to 70 with a mean age of 28.4 years. In more than 60% of cases, the lesions were on the face. By histopathological examination, 86 of 100 patients were positive for CL; while FNAC showed 77 cases as positive for CL. Taking histopathology as a standard diagnostic procedure, FNAC showed a remarkably high sensitivity (89%) and specificity (100%). The positive and negative predictive values were 100% and 60%, respectively. CONCLUSION: FNAC is easier, less painful and more cost effective than the conventional 'scraping method/biopsy followed by histopathology'. The high sensitivity and specificity eliminate the need for other time consuming and invasive procedures. Limitations include poor sampling and poor yield.

Adolescent↗