Iron Deficiency Anemia as a Risk and Prognostic Factor of Community Acquired Pneumonia

Background: Community Acquired Pneumonia (CAP) is a major cause of morbidity and mortality. While there is much data about risk factors for severe outcome in the general population, there is less focus on iron deficiency anemia as a risk and prognostic factor among these patients. Therefore, we aimed to detect simple prognostic factors for severe morbidity and mortality in patients with CAP. Patients and Methods: This study was done on 110 patients with ages ranged between 35 and 60 years who were diagnosed with CAP (defined as pneumonia identified in persons who have not been hospitalized recently). This study was carried out in Internal Medicine and Chest Departments, Al-Azhar Assiut University Hospital, over a period from April 2013 to January 2014. CRP, CBC and iron profile were done for all patients. Results: The cohort included 110 patients with mortality rate was 8.18% (9 cases) and the mean length of stay was 16.22±1.25 days. In univariate analysis, patients those with co-morbid conditions tended to have complicated disease. In multivariate analysis, variables associated with complicated hospitalization included Blood Urea Nitrogen (BUN) 30 mg/dL, creatinine 1.3 mg/dL, CRP 6mg/L, Hb 1 1g/dL, abnormal White Blood Cells (WBC) and elevated RDW. Iron level was decreased in complicated than uncomplicated cases (32.47±7.43 vs 57.72±8.65ug/dL) (p 0.001). TIBC was lower in complicated than uncomplicated cases (225.04±15.26 vs 257.10±9.84ug/dL) (p 0.001), with increase in serum ferritin in complicated than uncomplicated cases (70.21±26.78 vs 30.25±13.94 ng/mL) (p 0.001). Serum iron showed negative linear correlation with CRP (r=–0,765; p 0.0001) and ferritin (r=–0.658; p 0.0001). Conclusions: Iron deficiency is common in patients with CAP and it is associated with significant higher rates of mortality and severe morbidity. RDW is a good and cheap prognostic marker for CAP on admission. There is an excellent inverse correlation between serum iron and CRP during decline in infection.