Changing epidemiology, clinical features, and outcome of acute community-acquired pneumonia among adults in India

Abstract number: 1134_02_83

Tariang D.D., Ajaykumar A., Brahmadattan K.N., Lalitha M.K., Paul N., Zachariah A., Abraham O.C., Song J.-H., Mathai D.

Background:

Acute CAP is the third leading cause of mortality in India. Two prospective studies from our centre identified common causes of CAP in India to be Mycoplasma pneumoniae [MP] and Legionella pneumophila [LP] by serology in 11% each, and SPN in 10% by culture of respiratory secretions/blood/pleural fluid among 125 patients [pts] in the year [y] 1994; and Chlamydia pneumoniae [CP] in 6.5% among 80 pts in y 1998.

Methods:

In a 14-month prospective study ending June 2003, 100 consecutive adults hospitalized with CAP were studied for epidemiology and mortality, and compared with data from previous studies.

Results:

Among 100 pts [age 15–84 yrs], 21 were elderly [age > 65 yrs]. There were 63 males. Risk factors included: bronchopulmonary diseases (34 pts), cardiovascular (15), liver and renal (9 each), non pulmonary neoplasms (4), and cerebrovascular accidents (2).

Cultures in 55 yielded: SPN (13) Klebsiella spp [KP] (12); PSA (9); Haemophilus influenzae [HI] and Staphylococcus aureus [SA] (5 each); and others (11). CP was detected serologically in 24% and LP urinary antigen was negative in all. SPN isolates were uniformly susceptible to PCN [table 1].

Mortality was 15%. Patients infected with PSA had the highest mortality (44.4%) > HI (40%) > KP (25%) and CP (12.5%). None infected with SPN or SA died. Pneumonia Outcome Research Team [PORT] risk classes I and II had low mortality (3.2%) compared to III (18.8%), IV (22.2%), and V (63.6%). Factors significantly associated with mortality included: renal failure [creatinine >1.4 mg/dL] (OR 8.3, 95% CI 1.5–44.4); tachypnea [rate >30/mt] (OR 5.6, 95% CI 1.5–21.1); PSA associated pneumonia (OR 5.8, 95% CI 1.1–30.9). Mortality in 1994 and 1998 was 3/125 and 5/80 respectively. Initial treatment was with PCN in 28 and flouroquinolones [FQR] in two.

Table 1 Susceptibility of SPN Isolates to commonly used antibodies for CAP

Conclusion:

Although SPN is the most common isolate, the rising numbers of gram negative organisms (38%) and atypical pathogens associated with increasing mortality stress the need for review of initial antibiotic choice for adults with higher PORT classes. In view of enduring susceptibility of SPN to PCN and minimization of resistance with narrow spectrum activity, this should be the drug of choice for SPN in India. FQR that has a wide coverage against most respiratory pathogens including atypicals, can be considered as an initial choice in both hospitalized and ambulatory setting. Continued surveillance of respiratory pathogens is needed.