RESUMEN
OBJECTIVE: Pseudomembranous colitis (PMC) is well recognized as an important cause of diarrhoea in patients receiving antibiotics, with significant consequences of morbidity and mortality. Mortality among elderly patients is high, and even with successful treatment, a significant number of patients relapse. To evaluate the outcome of elderly patients with PMC, and to try to identify risk factors that might influence mortality or relapse. METHOD: We studied 72 consecutive hospitalized patients with endoscopically proven PMC. The medical records of all patients with their clinical history and laboratory data were reviewed in detail. These data included: pre-hospitalization residence and physical status, background medical history, presenting symptoms, antibiotic history, haematological and biochemical parameters, treatment, duration of hospitalization, complications, mortality within 30 days of hospitalization and relapse. RESULTS: Of the 72 patients (M/F=34/38, mean age=77 years), 47% were nursing home residents. Prior to hospitalization, 91.6% of patients had received antibiotic treatment (cephalosporins - 64%, penicillins - 42% and quinolones - 28%), 26% of patients received antacid therapy and 36% had been fed with a nasogastric tube (NGT). Thirty-seven (51%) patients recovered without complications, 21 (29%) patients died within 30 days of hospitalization and 14 (19%) patients were re-hospitalized because of relapse of PMC. Multivariate analysis revealed that white blood cell count above 20 x 10(3)/mm3 (P=0.009), serum albumin level of less than 2.5 g/dl (P=0.02), and pre-hospitalization NGT feeding (P=0.01) were associated with high mortality. Treatment with acid-reducing drugs (P=0.01) and living at a nursing home (P=0.06) were associated with high relapse rates. CONCLUSION: Pseudomembranous colitis is an important complication of antibiotic therapy and is associated with high mortality and recurrence rate, especially in old and debilitated persons. Pre-admission NGT feeding, severe leucocytosis and hypoalbuminaemia on admission are associated with increased mortality. Pre-hospitalization acid reducing treatment and nursing home residency are associated with increased risk of recurrence.