A 5-year 6-month-old Mexican-American boy with cystic fibrosis and a past medical history of chronic sinusitis and pulmonary disease was admitted to the Christus Santa Rosa Children’s Hospital for evaluation of recurrent fever and pneumonia.
The patient was first diagnosed as having cystic fibrosis when he presented at the age of 2 years 6 months with pneumonia, failure to thrive and pancreatic insufficiency. His disease process was stable until 6 months before referral to our institution. During this 6-month interval, he had been hospitalized at a local hospital because of episodes of fever, worsening cough and decreased exercise tolerance on six separate occasions. At each admission sputum cultures had yielded mucoid Pseudomonas aeruginosa, Stenotrophomonas maltophilia, and Candidaalbicans. Chest radiographs obtained at each admission consistently demonstrated bilateral upper and lower lobe infiltrates. During each of his six hospitalizations, he received an antibacterial regimen consisting of an antipseudomonas beta-lactam antibiotic, trimethoprim-sulfamethoxazole, aggressive pulmonary toilet and nutritional support, which resulted in resolution of fever, decreased cough, improved exercise tolerance and weight gain. However, within time periods no greater than 4 weeks after each hospital discharge, recurrence of symptoms obligated readmission to the hospital.
Within 1 week after discharge following his sixth and most recent hospitalization, he again developed fever, worsening cough and decreased exercise tolerance. Trimethoprim-sulfamethoxazole was initiated as an outpatient oral regimen with the presumption that pulmonary infection caused by S. maltophilia, which had been present in his sputum cultures during the course of his six hospitalizations, was the etiology of recurring fevers and worsening pulmonary symptoms. He defervesced and his respiratory symptoms improved during the 2-week course of trimethoprim-sulfamethoxazole therapy but developed fever within 1 week of treatment cessation. He was then referred to our institution for evaluation.
Past medical history was significant only for the recurrent hospitalizations because of fever and pneumonia and for chronic sinusitis. There was no family history of cystic fibrosis, primary immunodeficiency, episodes of recurring fever or unusual infections. The patient did not have any known exposure to tuberculosis and had no recent contact with persons who had significant illness. He was born, had lived and traveled only within the region of south Texas. The patient resided with his mother and attended first grade, where he was doing well. His immunizations were current.
On his evaluative admission to Christus Santa Rosa Children’s Hospital, his temperature was 36.4°C, pulse 119 beats/min, respiratory rate 26 breaths/min, blood pressure 85/59 mm Hg, and transcutaneous oxygen saturation was 95 to 96% while breathing room air. He weighed 18.6 kg (∼25th percentile), and his height was 115 cm (50 to 75th percentile).
Physical examination revealed a slender boy in no acute distress who had unlabored respiration. Examination of the chest identified crackles at the left posterior lung base. Cardiac and abdominal examinations were unremarkable. His skin color was acyanotic, and he had no significant cutaneous lesions. He had clubbing of the fingers and toes. He was alert, oriented and appropriately responsive.
Complete blood count revealed a total white blood cell count of 21.1 × 109/l, consisting of 62% polymorphonuclear leukocytes, 28% lymphocytes, 7% monocytes, 2% eosinophils and 1% basophils. He did not have serum antibodies against human immunodeficiency virus. Purified protein derivative skin testing for tuberculosis administered at the time of admission was nonreactive. Pulmonary function tests indicated a 1-s forced expiratory volume of 44% of vital capacity and a midexpiratory (25 to 75%) forced expiratory flow rate of 32% of predicted normal value, which indicated moderate restrictive and obstructive pulmonary dysfunction.
Chest radiograph obtained at admission revealed a dense consolidation with central cavitation in the left lower lobe and an area of cavitation with discrete parenchymal nodules in the right upper lobe. Computed tomography of the chest, obtained at admission and compared with one obtained 2 months previously, indicated progressive pulmonary disease, with nodular changes in the right upper lobe, worsening left lower lobe consolidation and the development of several cavities in the left lower lobe, the largest of which exceeded 1 cm in diameter.
Culture of sputum yielded mucoid P. aeruginosa. Two sets of blood cultures obtained during separate episodes of fever that occurred during the first 2 days of hospitalization were sterile.
The patient was treated with piperacillin-tazobactam and tobramycin, which were initiated empirically at the time of admission and continued after susceptibility of the sputum isolate was confirmed. The patient was also treated with levalbuterol, inhalational dornase-alpha, montelukast, loratadine, pancrelipase, budesonide nasal spray and nebulized tobramycin. Despite therapy the patient continued to have sustained fever during the first week of hospitalization, reaching a maximum temperature of 38.3°C during that time.
Because of persistence of fever, bilateral bronchial lavage and bilateral sinus drainage was performed. Bacterial culture of the sinus drainage yielded mucoid P. aeruginosa that was susceptible to the current antimicrobial regimen. Bronchial lavage specimen from the right and left lower lobes yielded mucoid P. aeruginosa, alpha-hemolytic Streptococcus and an unexpected organism. Antiinfective therapy was modified in response to this finding, and the fever resolved by the third day of treatment.