Respiratory syncytial virus pneumonia complicated by Streptococcus pneumoniae co-infection: two case reports and an analysis of their opposite outcomes

Background: Outcome prediction in critically ill patients is difficult but important for the appropriate allocation of resources. This case report describes opposite outcomes in a married couple despite their same age and health condition, type of infection and inflammatory response. Established scoring methods assist in precise prognostication. Case Description: We report the cases of a married couple, both 80 years old, former cigarette smokers (15 pack-years each) with inconspicuous past medical history requiring no long-term medication. They presented with productive cough, fever, shortness of breath and pleuritic chest pain. Laboratory tests showed highly elevated inflammatory parameters and arterial blood gas analysis revealed hypoxemic respiratory insufficiency. Extensive bilateral pneumonic infiltrates were documented by computed tomography scans. Both shared evidence of respiratory syncytial virus (RSV) infection by nasal swab and growth of S. pneumoniae in blood cultures confirming the diagnosis of an RSV pneumonia complicated by S. pneumoniae co-infection. Patient 1 (wife) was managed on the general ward and 1.2 g amoxicillin/clavulanic acid was administered intravenously every eight hours. She was discharged after 8 days. Antibiotic treatment was continued for another two days (625 mg orally three times a day). Patient 2 (husband) was also treated with amoxicillin/clavulanic acid initially, at a dose adjusted to his impaired renal function of 1.2 g every 12 hours. He was transferred to the intensive care unit (ICU), as he required mechanical ventilation, vasopressors and continuous veno-venous hemodiafiltration. Ventilator-associated pneumonia was diagnosed on day 5, and therapy escalated to piperacillin/tazobactam 4 g/0.5 g every eight hours for 14 days. As there was no organ function recovery and according to the patient's advance directive, therapy was changed to palliation. He died on day 24. SOFA, APACHE II and SAPS II scores were calculated. The predicted mortality risks were 0%, 15% and 10.6% for patient 1, and 50%, 55% and 75.3% for patient 2. Conclusions: The number and degree of organ dysfunctions as measured by ICU scoring systems identified patient 2 as a high-risk patient and prognosticated his outcome. Male sex, hormone levels (not measured), acute kidney failure, and nosocomial pneumonia might have contributed to his mortality. Pneumococcal and RSV vaccinations should be promoted in the elderly.