Molecular diagnosis of cystic fibrosis in Indian patients--a preliminary report.

AIM: The aim of the study was to screen for the common deltaF508 mutation and the poly T polymorphism and to determine their frequency in the cystic fibrosis transmembrane conductance regulator (CFTR) gene among the suspected CF cases referred to our clinical care centre for sweat chloride tests. METHODOLOGY: Sweat and EDTA blood samples were obtained from 23 clinically suspected cystic fibrosis (CF) cases. Sweat was estimated by pilocarpine iontophoresis procedure. Poly T polymorphism was detected by the multiplex-PCR based on ARMSTM technique and deltaF508 mutation by PCR-mediated site-directed mutagenesis method. RESULTS: Five cases, mainly with respiratory abnormalities and followed by steatorrhea had elevated sweat chloride levels (> 60 mmol/l), three of them, each with nutritional, respiratory and pancreatic abnormalities were borderline (40-60 mmol/l) and the remaining 15 clinically suspected CF cases had normal sweat chloride levels (< 40 mmol/l). The 9T variant was frequently observed (75%) in cases with elevated sweat chloride, including those exhibiting borderline values; with no 5T variant. The 7T was the most common variant (77%) observed in the cases with normal sweat chloride, with only one 5T variant (33%). Of the five cases with high sweat chloride, four cases were homozygous for deltaF508, whereas one was heterozygous with borderline sweat chloride, thus showing an overall frequency of 56.25% in the CF chromosome. DeltaF508 was found to be present with the 9T variant in all the instances. CONCLUSION: The presence of the 9T variant along with elevated sweat chloride levels can be used to predict a high risk of the individual harboring the severe deltaF508 mutation. It would be advisable to test for to the deltaF508 mutation along with the sweat chloride estimation in all the critically suspected CF cases diagnose CF with a higher degree certainty.

Effect of tense ascites on esophageal body motility and lower esophageal sphincter pressure.

BACKGROUND: Esophageal motility and lower esophageal sphincter (LES) pressure change with rapid changes in intraabdominal pressure (IAP); the response of these to slow change in IAP is not known. AIMS: To study esophageal body motility and LES pressures in patients with cirrhosis with tense ascites in the basal state and after paracentesis. METHODS: Twenty four patients with cirrhosis of liver and tense ascites and 13 with cirrhosis without ascites (controls) were studied. Basal intragastric (IGP) and LES pressures, and esophageal body response to water swallows, were recorded using a water perfusion system; IAP was measured in patients with ascites. In patients with ascites, the study was repeated twice: after paracentesis of two liters of fluid and after adequate control of ascites. RESULTS: Basal IGP (p = 0.002) and duration of esophageal contraction (p = 0.01) were lower in controls, but basal LES pressures were similar in the two groups. After control of ascites, IAP (p = 0.02) and IGP (p = 0.005) decreased; amplitude and duration of distal esophageal contraction decreased (p < 0.05). The frequency of high-amplitude waves also decreased (p = 0.04). LES pressure remained unaltered. CONCLUSIONS: Esophageal contraction duration is increased in the presence of ascites, and decreases after control of ascites; LES pressure is not affected by ascites.

Manometric mapping of normal esophagus and definition of the transition zone.

BACKGROUND: The normal esophagus has not been manometrically mapped. The transition zone between esophageal smooth and skeletal muscles has also not been defined manometrically. AIMS: To manometrically map the normal esophagus and to define the transition zone. METHODS: Thirty normal adults [23 men; mean age 34.8 (10.4) years] underwent manometry using a water-perfused system. The lower esophageal sphincter (LES) was studied by station pull-through, and esophageal body musculature was evaluated at 1-cm intervals with five wet swallows at each level. The transition zone was identified as an area where the wave-forms did not resemble typical skeletal or smooth muscle wave-forms. RESULTS: The basal mid-expiratory LES pressure was 18.7 (7.2) mmHg, and its length was 3.6 (1.2) cm. Based on our findings, we defined the transition zone as an area where either the amplitude of contraction was < 40 mmHg or, if the amplitude was 40-50 mmHg, the rate of change of pressure from baseline to peak of the wave was < 50 mmHg/s. The lengths of the skeletal, transition and smooth muscle zones were 2.8 (1.2), 4.0 (1.7) and 12.5 (2.7) cm, respectively. The amplitude and dp/dt of contraction and transmission velocity were lowest in the transition zone (p < 0.05). CONCLUSIONS: We have manometrically mapped the normal esophageal muscle zones; the parameters obtained may be used as reference values. The manometric criteria for the transition zone have also been defined.