Comparison between Fluorescence in-situ Hybridization (FISH), Reverse Transcriptase PCR (RT-PCR) and fragment analysis, for detection of t (X; 18) (p11; q11) translocation in synovial sarcomas

Background: Synovial sarcoma (SS) is an aggressive, but a relatively chemosensitive soft tissue sarcoma, characterized by a specific, t (X;18)(p11;q11) translocation, leading to formation of SS18–SSX chimeric transcript. This translocation can be detected by various techniques, such as fluorescence in-situ hybridization (FISH), reverse transcriptase PCR (RT-PCR) and fragment analysis. Objectives: To compare the results of detection of t (X;18)(p11;q11) translocation, across three different platforms, in order to determine the most optimal and sensitive technique. Methods: Formalin-fixed paraffin embedded (FFPE) tissue sections of 45 soft tissue sarcomas were analyzed, including 16 cases of SS confirmed by histopathology, immunohistochemistry and molecular technique (s)(Group 1); 13 cases, wherein SS was one of the differential diagnosis, preceding molecular testing (Group 2) and 16 cases of various other sarcomas (Group 3). Various immunohistochemical (IHC) markers studied, including INI1/SMARCB1. All cases were tested for t (X;18) translocation, by fragment Analysis, FISH and RT-PCR. Results: There were 23 cases of SS, including 16 of group 1 and 7 of group 2. By fragment analysis, t (X;18)(p11;q11) translocation was detected in 22/23 cases (95.6%). By FISH, SS18 gene rearrangement was detected in 18/22 cases (78.2%), whereas by RT-PCR, SS18-SSX transcripts were detected in 15/23 cases (65.2%). Immunohistochemically, a unique “weak to absent”/reduced INI1 immunostaining pattern was exclusively observed in 12/13 cases of SS (92.3%). Fragment analysis and FISH were relatively more sensitive techniques. Unique “weak to absent”INI1 immunoexpression significantly correlated with positive t (X;18) translocation results (P = 0.0001). Conclusion: The present study constitutes first such study from our subcontinent. Fragment analysis is a promising technique for detection of t (X;18)(p11;q11) translocation. FISH and INI1 immunostaining pattern were also relatively more sensitive, over RT-PCR.

Hypomagnesaemia in paediatric population in an intensive care unit.

AIMS: To determine incidence and risk factors for hypomagnesaemia in children admitted in Paediatric Intensive Care Unit, (PICU). SUBJECTS AND METHODS: Prospective study was carried out on 80 children admitted in PICU. The patients were clinically assessed for nutritional status, neurological status on Glasgow coma scale, congestive cardiac failure, etc. and relevant biochemical parameters including serum and red cell magnesium levels were done. 25 patients of the same age group admitted in general ward who were not in critical state were included as a control group. RESULTS: 70% of PICU patients had hypomagnesaemia, which was more common in patients on aminoglycosides and diuretics. CONCLUSION: In view of complications of magnesium depletion and benign nature of appropriate magnesium therapy critically ill children should have their magnesium level monitored.

Familial glucocorticoid deficiency, alacrimia and achalasia--Allgrove syndrome.

We report three brothers with Allgrove syndrome. All three had evidence of adrenal insufficiency and deficient tear production, though neither of them had achalasia, the third component of the disorder at the time of this report. Neurological abnormalities were present in the index case. The younger siblings were neurologically normal. The familial association of achalasia, alacrimia and adrenal insufficiency, rather than being fortuitous, is a distinct clinical entity.