بررسي 13 ساله فراواني و علائم باليني سندرم هموليتيك يورميك و ترومبوتيك ترمبوسيتوپنيك پورپورا در بيماران مراجعه كننده به مراكز درماني شيراز

A 13-Year Study on the Prevalence and Clinical Features of Hemolytic Uremic Syndrome and Thrombotic Thrombocytopenic Purpura in Patients Reffering to Shiraz University Hospitals

Objective: The hemolytic uremic syndrome (HUS) and thrombotic thrombocytopenic purpura (TTP) are rare disorders characterized by intravascular platelet aggregation and widespread thrombus formation in the microcirculation with resulting tissue ischemia. In spite of several studies on these disorders all over the world, their basic epidemiology and clinical aspects are still obscure in Southwest of Iran. Subjects and Methods: We conducted a retrospective analysis of 136 patients with HUS or TTP hospitalized from April 1991 through March 2004 in 3 large hospitals of Shiraz (the largest referral city in Southwest of Iran) to evaluate their epidemiological aspects, clinical characteristics and laboratory findings. Results: One hundred and one cases of HUS (49 females and 52 males) and 35 cases of TTP (21 females and 14 males) were identified. The mean age was 3.5 years for HUS, and 30.8 years for TTP. The mean annual incidence rate of HUS decreased significantly from 8 cases in 1993 to 1.1 cases per 1,000,000 child in 2003 (p< 0.001). While the incidence rate of TTP increased from 0.6 cases in 1992 to 5.2 cases per 1,000,000 residents in 2003 (p< 0.05), a seasonal pattern was noted for both TTP and HUS cases, with the highest incidence in summer months. Twenty patients with HUS and 16 with TTP died, resulting in a case fatality rate of 19.8 and 45.7%. No prognostic factor was identified for TTP, while the presence of signs of neurological impairment and high leukocyte counts had an adverse effect on the prognosis of HUS patients. Conclusion: In contrast to other countries, in Southwestern Iran the incidence rate of HUS has a decreasing trend, which is probably related to the decrease in gastrointestinal diarrheal infections (especially E.coli 0157:H7) and their improved management. On the other hand, the incidence of TTP is increasing in Southwestern Iran as in other countries.