Mode of presentation and first line of management of non-recurrent urolithiasis in Kuwait

AIMS: To determine the incidence, mode of presentation, first line of management and composition of non-recurrent urolithiasis in Kuwait. METHODS: Consecutive patients admitted between January 1999 and December 2002 with non-recurrent urolithiasis were prospectively analyzed. RESULTS: The average annual incidence of hospital admission for non-recurrent urolithiasis in Kuwait was 43.44 per 100,000 population, representing men and women (ratio, 9:1) with a median age of 41.91 years. Of the hospital admissions for non-recurrent urolithiasis, 57.2% of cases were acute. Overall, the most predominant symptom was flank pain, while the least common symptom was acute urinary retention. Ureteroscopic stone manipulation was the most common initial treatment modality in the present series, as it was utilized in 43.3% and 37.09% for patients admitted on elective and emergency basis, respectively. Of the calculi available for chemical analysis, 91% contained calcium, 73% contained calcium oxalate, 17% contained mixed calcium and 1% contained calcium phosphate. The composition of the rest of the stones were urate in 7%, struvite in 1% and cystine in 1%. CONCLUSIONS: Urolithiasis is a common disease in the Kuwait region that mainly presents with flank pain. Ureteroscopic calculus removal is the most common modality of treatment. The majority of the calculi seen in Kuwait contained calcium.     

Studies on an Oral Iron Chelator: 1,2-Dimethyl-3-hydroxy-pyrid-4-one (DMHP). Mechanism of Intestinal Absorption in Rabbits

Abstract— Over the last 30 years, desferrioxamine has been the only iron chelator in clinical use. This chelator is expensive and must be given by injection. A new class of chelators, namely 1-alkyl-2-methyl-3-hydroxypyrid-4-ones, have been shown to be orally effective. Using 1,2 dimethyl-3-hydroxy-pyrid-4-one (DMHP), we have carried out a study to clarify the mechanism of intestinal absorption of this new class of drug, using an in-situ system of the intestine from rabbit. The major site of DMHP absorption is in the intestine and is linear with increasing drug concentration. DMHP absorption per unit length of jejunum and ileum is similar; however, due to the larger surface area of jejunum, the absorption by ileum segment is more effective per unit surface. l -Proline, l -tryptophan (amino acids), 2-deoxyglucose, and sodium iodoacetate (metabolic inhibitors) have no effect on DMHP absorption, but l -phenylalanine, an amino acid with a 6-member carbon ring, significantly inhibits the DMHP absorption from the intestinal segment. We conclude that the mechanism of DMHP absorption in the intestine is mainly by simple passive diffusion based on the linear relationship found between drug concentration and absorption. However, the inhibitive effect of l -phenylalanine suggests that the co-existence of a facilitated uptake cannot be ruled out.