Riaz Chowdhury
University of Florida
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Featured researches published by Riaz Chowdhury.
Pancreas | 2005
Riaz Chowdhury; Manoop S. Bhutani; Girish Mishra; Phillip P. Toskes; Chris E. Forsmark
Objectives: The diagnosis of “minimal change” chronic pancreatitis (MCCP) is often considered when conventional imaging studies are unrevealing in a patient population with abdominal pain of presumed pancreatic origin. Direct pancreatic function testing using secretin as a secretagogue (ST) has been considered the most sensitive method to diagnose MCCP but is not widely available to clinicians. Endoscopic ultrasound (EUS) allows detailed imaging of pancreatic architecture, but the sensitivity and specificity for MCCP remain to be determined. We sought to compare the accuracy of EUS and ST in patients with presumed MCCP. Methods: Seventy-four patients referred to our pancreas clinic with unexplained abdominal pain and previously negative imaging studies underwent an ST for evaluation of possible MCCP. Twenty-one of these also underwent EUS. EUS images were read by 1 of 2 experts blinded to ST results. Results: Using ST as the “gold standard,” EUS had a maximum sensitivity of 71% when the cut-off for diagnosis was set at at least 3 EUS features. Conversely, maximum specificity (92%) was seen when the cut-off value was set at at least 6 EUS criteria. Diagnostic certainty was only 50% (positive predictive value = 0.5) when at least 6 criteria were used as the cut-off. MCCP was excluded with greater than 70% certainty when less than 3 criteria were present. At the best cut-off value of at least 4 features, EUS had a sensitivity of 57% and a specificity of 64%. Conclusions: In this patient population with abdominal pain of presumed pancreatic origin, EUS and standard pancreatic function testing are often discordant. If ST is assumed to be the reference against which other tests are compared, EUS is less accurate than ST in diagnosing MCCP.
Pancreas | 2003
Riaz Chowdhury; Chris E. Forsmark; Richard H. Davis; Phillip P. Toskes; G. Nicholas Verne
Introduction The most common symptoms of chronic pancreatitis are abdominal pain, diarrhea, and weight loss. The abdominal pain has no consistent pattern, and nausea and vomiting commonly occur simultaneously. Gastroparesis may produce similar symptoms. These similar symptoms may cause diagnostic confusion, particularly with regard to patients with small-duct chronic pancreatitis, for whom diagnosis of chronic pancreatitis is most difficult. We have observed that coexistent gastroparesis may also interfere with the effectiveness of pancreatic enzyme therapy by failing to deliver proteases into the duodenum and therefore not restoring feedback control of pancreatic secretion. Aim To estimate the prevalence of gastroparesis in patients with minimal-change chronic pancreatitis. Methodology Patients with chronic pancreatitis diagnosed on the basis of secretin test results but with otherwise normal pancreatic imaging (ultrasonographic or computed tomographic) findings who had also undergone a gastric emptying study were retrospectively identified. An abnormal secretin test value was defined as a peak bicarbonate concentration in pancreatic secretions of <80 mEq/L after secretin stimulation. Gastroparesis was defined as an emptying half-time greater than 90 minutes. Results Fifty-six patients were identified. Twenty-five of the 56 patients (44%) had concomitant gastroparesis and small-duct chronic pancreatitis. Twenty-four of these 25 were women, and 22 of the 25 had idiopathic small-duct chronic pancreatitis. Conclusion In our referral population, gastroparesis is frequently seen in patients with small-duct chronic pancreatitis. For patients with small-duct disease whose abdominal pain does not respond to pancreatic enzyme therapy, clinicians should consider an evaluation for gastroparesis.
Pancreas | 1998
Koji Ochi; Naoki Matsumura; Ryoichi Yamamoto; Riaz Chowdhury; Takaaki Mizushima; Juntaro Tanaka; Hideo Harada
Prolyl hydroxylase is a key enzyme in collagen synthesis, and tissue inhibitor of metalloproteinase (TIMP) is known to suppress collagenolytic enzymes. To see whether the levels of these two enzymes in serum and human pure pancreatic juice (PPJ) are good indicators of pancreatic fibrosis in chronic pancreatitis (CP), we examined 15 controls, 14 alcoholics without evident pancreatic diseases (7 current drinkers and 7 former drinkers), and 19 patients with CP. Levels of the two enzymes were determined by a sandwich enzyme immunoassay method. TIMP-1 levels in PPJ were significantly higher in patients with CP than in controls and alcoholics, with overlap in only a few exceptional patients. A significant inverse correlation between TIMP-1 and bicarbonate output in PPJ was observed. Prolyl hydroxylase levels in PPJ, in contrast, were significantly higher in current drinkers than in patients with CP, controls, and former drinkers, with overlap in only a few exceptional patients with relapsing CP. Identical results were obtained even when the enzyme levels were expressed as nano-grams per milligram of protein. Serum levels of prolyl hydroxylase and TIMP-1 showed no significant differences among controls, current alcoholics, former alcoholics, and patients with CP. These results indicate that the raised level of TIMP-1 in PPJ, unlike that of prolyl hydroxylase, is a good indicator of pancreatic fibrosis in CP.
The American Journal of Gastroenterology | 2000
Riaz Chowdhury; Girish Mishra
A plea for prophylactic antibiotics prior to endoscopic ultrasound (EUS)-guided FNA in cirrhotic patients: yet another etiology for spontaneous bacterial peritonitis (SBP)
Gastroenterology | 2001
Riaz Chowdhury; Manoop S. Bhutani; Girish Mishra; Chris E. Forsmark; Phillip P. Toskes
Gastroenterology | 2001
Riaz Chowdhury; Chris E. Forsmark; Manoop S. Bhutani; Phillip P. Toskes
Gastroenterology | 2001
Riaz Chowdhury; Manoop S. Bhutani; Chris E. Forsmark; Phillip P. Toskes
岡大三朝分院研究報告 | 1995
Riaz Chowdhury; Koji Ochi; Hideo Harada; Juntaro Tanaka; Takaaki Mizushima; Shuji Matsumoto; Toshinobu Seno; Mitsuko Ichimura; Tsuneo Akiyama; Satoshi Yokota
Gastroenterology | 1995
S. Matsumoto; Hideo Harada; J. Tanaka; Koji Ochi; Riaz Chowdhury; Tetsuya Tsurumi
岡大三朝分院研究報告 | 1994
Riaz Chowdhury; Koji Ochi; Juntaro Tanaka; Shooji Matsumoto; Toshinobu Senou; Hideo Harada; Takaaki Mizushima; Yoshiro Tanizaki