Pneumonia

Necrotizing Pneumonia

Mairelys Gonzalez, MD; Joanne Holliman, MD; Betzi Teran, MD; Magda Mendez, MD; Yekaterina Sitniskaya, MD; and Elita Gose-Balakrishnan, MD

Lincoln Medical and Mental Health Center, Bronx, New York

A 19-month-old boy known to have intermittent asthma and a history of prior right lower-lobe pneumonia presented to the emergency department (ED) with a 1-week history of cough, runny nose, chest retractions, and rapid respirations. The boy also had had episodes of fever for the past 3 days and posttussive vomiting with decreased oral intake.

On arrival to the ED, the child had a temperature of 39.9°C, a tachycardic heart rate of 160 beats/min, tachypneic respiratory rate of 60 breaths/min, and an oxygen saturation of 96% on room air.

On physical examination, no retractions were noted, but he had fair air entry and bilateral wheezing with prolonged expiration. The child was managed initially with albuterol/ipratropium nebulization, oral corticosteroids, and ibuprofen for fever, resulting in some improvement of the respiratory rate.

chestBefore the patient was admitted to the pediatric ward owing to the persistence of respiratory distress, a complete blood count was done and was remarkable for a white blood cell count of 30,500/µL. On admission, physical examination findings showed decreased air entry on the right side, but no wheezing. Chest radiography was ordered, and the patient was started with intravenous cefuroxime. The radiographs later showed extensive pneumonia involving two-thirds of right lung with right-sided effusion. The C-reactive protein level was elevated at 119 mg/L.

During his hospital stay, intravenous antibiotic coverage was changed to ceftriaxone. Vancomycin and rifampin were added owing to the multilobar pneumonia and small parapneumonic effusion, which most likely represented a secondary bacterial etiology (eg, pneumococci, Staphylococcus aureus). Results of chest ultrasonography showed minimal free right pleural effusion insufficient for thoracocentesis.

Chest computed tomography (CT) found extensive right middle and right lower lobe infiltrates with areas of lucency suggestive of necrotizing pneumonia, without reduced pulmonary volume, no significant pleural collections, and no abscess.

The patient received intravenous antibiotics for a total of 14 days and was discharged on a regimen of oral cefpodoxime for 14 more days. At time of discharge, repeated chest radiographs showed improvement of the large consolidation of the middle and lower right lung, and on physical examination, he had good air entry bilaterally.

After discharge, the patient was followed up by infectious disease and pulmonology specialists, with resolution of pneumonia on clinical evaluation and chest radiography. The latest chest radiographs, taken 1 month after admission, showed that the right middle and lower lobes had reexpanded, with residual pleural density in the periphery and residual atelectasis, but the consolidation had mostly resolved.

headThe clinical course of community-acquired pneumonia in children usually is benign, and the condition responds well to conventional treatments. In some cases, bacterial pneumonia is complicated with pleural effusion, empyema, abscesses, pneumatocele, or necrotizing pneumonia. Necrotizing pneumonia is thought to be a consequence of pulmonary gangrene, tissue liquefaction, and subsequent necrosis. Necrotizing pneumonia caused by staphylococci has been associated with the cytotoxin Panton-Valentine leukocidin. The virulence factor M protein has been associated with tissue necrosis in group A streptococci.1

The diagnosis of necrotizing pneumonia can be suspected on plain chest radiographs if collections are seen with consolidations of lung or pleural fluid collections; however, the presence of dense tissue consolidation may obscure these findings. CT findings may include cystic cavities and decreased parenchymal enhancement after intravenous administration of contrast.2

References:

1.Sawicki GS, Lu FL, Valim C, Cleveland RH, Colin AA. Necrotising pneumonia is an increasingly detected complication of pneumonia in children. Eur Respir J. 2008;31(6):1285-1291.

2.McGrath B, Rutledge F, Broadfield E. Necrotising pneumonia, Staphylococcus aureus and Panton-Valentine leukocidin. J Intensive Care Soc. 2008;9(2):170-172.

3.Kreienbuehl L, Charbonney E, Eggimann P. Community-acquired necrotizing pneumonia due to methicillin-sensitive Staphylococcus aureus secreting Panton-Valentine leukocidin: a review of case reports. Ann Intensive Care. 2011;1(1):52.