Bordetella bronchiseptica pneumonia in a kidney-pancreas transplant patient after exposure to recently vaccinated dogs.

Bordetella bronchiseptica is an uncommon cause of respiratory infection in humans generally occurring in immunocompromised individuals exposed to infected animals. A 61-year-old female underwent a kidney-pancreas transplant 7 years before presentation. Postoperative immunosuppression was achieved with sirolimus and mycophenolate mofetil. The patient was doing well until she developed a small bowel obstruction secondary to adhesions. She underwent surgical adhesiolysis without complications. Two weeks postoperatively the patient developed pneumonia. She failed to respond to repeated courses of antibiotics, and thus, diagnostic bronchoscopy with bronchoalveolar lavage (BAL) was performed. BAL cultures grew B. bronchiseptica. Further investigation revealed that the patient's dogs had recently received a live-attenuated B. bronchiseptica intranasal vaccination. The patient recovered after 21 days of therapy with doxycycline based upon in vitro susceptibility testing. B. bronchiseptica is an uncommon but recognized human pathogen. It most commonly affects immunocompromised individuals. Here, we report a culture-proven case of B. bronchiseptica pneumonia in an immunocompromised host residing in a household with her dogs who had recently received live-attenuated, intranasal B. bronchiseptica vaccinations. As polymerase chain reaction testing was not performed comparing the isolated strain to the vaccination strain, the association is presumptive. This report expands the spectrum of immunocompromised hosts to include renal-pancreas transplant patients who have developed infection from B. bronchiseptica, while illustrating the risks associated with animal contacts and attenuated vaccines in the immunosuppressed population.

A single-season prospective study of respiratory viral infections in lung transplant recipients.

The frequency and complications of respiratory viral infections (RVI) were studied in 50 ambulatory lung transplant patients during a single winter season, using viral antigens, viral cultures and PCR of nasal washes or bronchoalveolar lavages. Patients' survival, episodes of acute rejection and occurrence of bronchiolitis obliterans (BO) or BO syndrome (BOS) were monitored for 1 yr after the study. Overall, 32 (64%) patients had 49 symptomatic episodes. Documented infections included eight due to respiratory syncytial virus (RSV), one due to parainfluenza virus (PIV) and 10 due to influenza (FLU). Four of the FLU infections were serological rises without symptoms. Overall, 17 (34%) patients had documented viral infection; four patients had lower respiratory involvement and two (one RSV, one PIV) were hospitalised for aerosolised ribavirin treatment. After 1 yr there were three (6%) deaths unrelated to RVI. BO or BOS had occurred in one (6%) out of 17 patients with and three (12%) out of 33 without RVI. Respiratory viruses infected one-third of ambulatory lung transplant recipients in a single season. In conclusion, respiratory viral infection was not associated with subsequent graft dysfunction. Larger prospective studies are required to better define the acute and long-term morbidity of these infections.

Active CMV infection before lung transplantation: risk factors and clinical implications.

BACKGROUND: Cytomegalovirus (CMV) infection is a major cause of morbidity following lung transplantation, but active CMV infection has not been described before transplantation. Since 1990, we have screened all lung-transplant recipients for CMV infection with viral urine cultures on the day of transplantation. We retrospectively reviewed the medical records of all 102 lung-allograft recipients transplanted between March 1990 and September 1998. Patients with positive urine cultures for CMV were compared to culture negative patients for age, gender, pretransplant diagnosis, time from diagnosis to transplantation, CMV serostatus, use of pretransplant immunosuppression, T-lymphocyte subsets, and presence of fever. Posttransplant outcomes assessed were duration of intubation and hospitalization, acute rejection, frequency of CMV disease, duration of Nashville rabbit antithymocyte serum or globulin (N-RATS/G) and ganciclovir, and survival. Five (5%) of 102 patients had positive urine cultures for CMV; none had symptoms of CMV infection. All 5 had idiopathic pulmonary fibrosis (IPF) (5/5 vs 27/97; p = 0.002). The age, gender, and CMV serostatus of these patients did not differ from the 97 patients in the culture negative group. Four (80%) of the 5 patients with positive cultures were receiving treatment with azathioprine or cyclophosphamide vs only 18 (19%) of the 97 patients with negative cultures (p = 0.007), and all 5 (100%) were receiving steroids compared to 50 (52%) of 97 patients with negative cultures (p = 0.06). Culture-positive IPF patients, when compared with the 27 culture-negative IPF patients, did not differ in any demographic variable or in the use of immunosuppression, but culture-positive patients were more likely to have a CD4/CD8 T-cell subset ratio <1.0 (p = 0.02). Following transplantation, 3 (60%) of 5 IPF patients with positive CMV cultures developed CMV disease compared to 3 (11%) of 27 IPF patients with negative cultures (p = 0.03). Patients with positive cultures also received more days of parenteral antiviral therapy (mean 44 +/- 11 days vs 16 +/- 10 days; p < 0.001). Utilizing pretransplant screening, we have discovered that 16% of patients with IPF had active CMV infection, which was associated with both alterations in their T-cell subsets and a greater risk for CMV disease after transplantation. This occurrence of occult CMV infection in patients with IPF has not been previously recognized, and has important implications.