Marita Gilljam

Molecular Epidemiology of Mycobacterium abscessus, with Focus on Cystic Fibrosis

ABSTRACT Mycobacterium abscessus has been isolated increasingly often from the respiratory tracts of cystic fibrosis (CF) patients. It is not known whether these organisms are transmitted from person to person or acquired from environmental sources. Here, colony morphology and pulsed-field gel electrophoresis (PFGE) pattern were examined for 71 isolates of M. abscessus derived from 14 CF patients, three non-CF patients with chronic respiratory M. abscessus infection or colonization, one patient with mastoiditis, and four patients with infected wounds, as well as for six isolates identified as environmental contaminants in various clinical specimens. Contaminants and wound isolates mainly exhibited smooth colony morphology, while a rough colony phenotype was significantly associated with chronic airway colonization (P = 0.014). Rough strains may exhibit increased airway-colonizing capacity, the cause of which remains to be determined. Examination by PFGE of consecutive isolates from the same patient showed that they all represented a single strain, even in cases where both smooth and rough isolates were present. When PFGE patterns were compared, it was shown that 24 patients had unique strains, while four patients harbored strains indistinguishable by PFGE. Two of these were siblings with CF. The other two patients, one of whom had CF, had not had contact with each other or with the siblings. Our results show that most patients colonized by M. abscessus in the airways have unique strains, indicating that these strains derive from the environment and that patient-to-patient transmission rarely occurs.

Lung transplantation in patients with cystic fibrosis and Mycobacterium abscessus infection

Mycobacterium abscessus lung disease is difficult to treat and has been considered a strong relative contraindication to lung transplantation. We performed double lung transplantation in three cystic fibrosis patients with ongoing, and a fourth with recent treatment for Mycobacterium abscessus lung infection. Despite prolonged antibiotic courses and adjustment of immunosuppressive therapy the first three patients developed skin infection and abscesses. At follow-up after 1, 3, 5 and 7years respectively no patient had evidence of M abscessus infection and all had stable lung function. Lung transplantation in patients with M abscessus lung infection is feasible but may involve severe complications.

Epidemiology of nontuberculous mycobacteria among patients with cystic fibrosis in Scandinavia

Background Nontuberculous mycobacteria (NTM) are an emerging threat to cystic fibrosis (CF) patients but their epidemiology is not well described. Methods In this retrospective observational study we identified all Scandinavian CF patients with a positive NTM culture from airway secretions from 2000 to the end of 2012 and used national CF databases to describe microbiological and clinical characteristics. Results During the 13-year period 157 (11%) CF patients were culture positive for NTM at least once. Mycobacterium abscessus complex (MABSC) (45%) and Mycobacterium avium complex (MAC) (32%) were the predominant species with geographical differences in distribution. Younger patients were more prone to MABSC (p < 0.01). Despite treatment, less than one-third of MABSC patients with repeated positive cultures cleared their infection and a quarter had a lung transplant or died. Conclusion NTM are significant CF pathogens and are becoming more prevalent in Scandinavia. MABSC and MAC appear to target distinct patient groups. Having multiple positive cultures despite treatment conveys a poor outcome.

Ultraviolet B radiation improves serum levels of vitamin D in patients with cystic fibrosis

BACKGROUND Ultraviolet B (UVB) radiation can be used in the prevention and treatment of vitamin D deficiency. AIM To investigate, in a controlled study of patients with cystic fibrosis (CF), whether regular UVB radiation would improve serum levels of calcidiol during the dark season (October-April). METHODS Thirty patients with mild to moderate disease were included (aged 9-40 y). All patients had cholecalciferol supplementation. One group (15 patients) was given UVB one to three times a week for 6 mo and one group (15 sex- and age-matched patients) served as controls. The radiation source consisted of three TL 12/40W UVB fluorescent lamps. Initial treatment duration was 1 min, subsequently increased by 0.5-1 min/treatment to a maximum of 10 min. RESULTS The mean initial serum calcidiol levels were 21 ng/ml in the controls and 22 ng/ml in the intervention group. Serum calcidiol levels increased to 44 ng/ml after 8 wk and to 50 ng/ml after 24 wk of UVB radiation; the corresponding serum levels in the controls were 19 and 25 ng/ml, respectively. The mean serum calcitriol levels increased in the treated group and were unaltered in the control group. CONCLUSIONS UVB radiation was effective in increasing vitamin D levels in patients with CF. The study results imply that UVB radiation is valuable in chronic conditions associated with vitamin D deficiency.

Extracorporeal membrane oxygenation as a bridge to lung transplantation: a long-term study

OBJECTIVES We investigated early outcomes in patients with end-stage pulmonary disease bridged with extracorporeal membrane oxygenation (ECMO) with the intention to perform lung transplantation (LTx). METHODS ECMO was used as a bridge to LTx in 20 patients between 2005 and 2013. Most patients suffered from rapid progress of disease and most failed to stabilize on mechanical ventilation. Sixteen patients (10 males, median age 42 years, range 25-59) underwent LTx after ECMO support for a median of 9 (range 1-229) days. Most patients were not on the waiting list while receiving ECMO, but after being assessed were on the waiting list for a median of 6 (range 1-72) days before LTx or death occurred. Median follow-up at 535 (range 36-3074) days was 100% complete, 9 patients have been followed for >1 year and 4 patients have been bridged during 2013. RESULTS Four patients died on ECMO waiting for a donor and as intention-to-treat, the success for bridging was 80% (16/20) and 1-year survival was 62% (10/16, not including 4 with <1-year follow-up). For those who underwent LTx, 3 patients died in-hospital after LTx on Days 0, 16 and 82, respectively, and currently, 11/16 (69%) are alive and 1-year survival for transplanted patients was 9/12 (75%). Median ICU stay before and after LTx was 9 (range 2-229) days and 20 (range 0-53) days, respectively. At follow-up, lung function was evaluated, and mean forced expiratory volume at 1 s and forced vital capacity were 56±22% of predicted and 74±24% of predicted, respectively. CONCLUSIONS ECMO used as a bridge to LTx results in acceptable survival in selected patients with end-stage pulmonary disease.

Co-morbidity of cystic fibrosis and celiac disease in Scandinavian cystic fibrosis patients

BACKGROUND The co-morbidity of cystic fibrosis (CF) and celiac disease (CD) has been reported sporadically since the 1960s. To our knowledge, this is the first time a systematic screening is performed in a large cohort of CF patients. METHODS Transglutaminase-IgA (TGA), endomysium-IgA (EMA) and total IgA in serum were measured in 790 CF patients (48% females, 86% with pancreatic insufficiency). Six patients were diagnosed with CD prior to the study, all receiving a gluten-free diet. Patients with elevated TGA (>50 Units/mL) and a positive EMA test were offered a gastroscopy obtaining mucosal biopsies from the duodenum. RESULTS Four new cases of CD were diagnosed. Two additional patients had positive serological tests, but normal biopsies. In total, 10 cases of CD (1.2%, 1:83) indicate a prevalence rate about three times higher than the general prevalence of CD in Norway and Sweden. No CD patients were detected in the Danish CF cohort. Patients diagnosed with untreated CD reported symptoms typical of both CF and CD (poor weight gain, loose and/or fatty stools, fatigue, irritability, abdominal pain). They improved after introduction of a gluten-free diet. CONCLUSIONS Systematic screening for CD in a Scandinavian cohort of CF patients revealed a higher prevalence of CD than in the general population. Clinical signs of CD are difficult to differentiate from CF with malabsorption, and patients may go undiagnosed for a long time. In a population where CD is common we recommend screening for CD in patients with CF.

Dietary intake and nutritional status in a Scandinavian adult cystic fibrosis-population compared with recommendations

Background Malnutrition is a well-known complication in cystic fibrosis (CF). There is good evidence that maintaining a normal body-weight correlates well with improved survival in CF. Energy intake in excess of 120% of the estimated average requirement (EAR) has been advised since 1980s. Objectives To investigate the nutritional intake and status in the adult Scandinavian CF-population. Subjects/Methods A cross-sectional multi-centre study was used to investigate the nutritional status of 456 adult CF-patients (2003 2006). Height and weight were measured and body mass index (BMI) and z-scores were calculated. Pulmonary function was examined by dynamic spirometry. A 7-day pre-coded food record (FR) obtained energy and nutrient intake data in 180 patients. Results The mean energy intake was 114 (SD 30.0)% of EAR and thus significantly lower than the target of 120% EAR (p< 0.001) for patients with pancreatic insufficiency (PI) (n=136). Mean BMI was 22.0 (SD 2.9), the prevalence of BMI <18 was 13% and the prevalence of BMI ≥25 was 15% (n=136). Mean BMI was 20.8 (SD 2.4) in PI-patients with FEV1 <70% and 23.2% (SD 3.0), in PI-patients with FEV1 ≥70%, mean difference 2.4, (95% CI: 1.5, 3.3) (p<0.001), but there was no difference in energy intake. BMI ≥18.5 and a reported energy intake <120% were revealed in 54% of the PI-patients. Conclusions The energy intake did not reach the recommended 120% EAR, but the prevalence of underweight was lower than reported in other studies. The recommendation may exceed the requirement for a number of CF-patients. The nutritional status must still be closely monitored and nutritional advice and intervention should be individualised and adjusted to actual needs.

Survival after lung transplantation for cystic fibrosis in Sweden

Objectives In Sweden, lung transplantation has been performed in patients with end-stage lung disease since 1990. We assessed survival after lung transplantation for cystic fibrosis (CF) with focus on early mortality and outcome for patients infected with certain multiresistant bacteria, considered a relative contraindication for lung transplantation. Methods Review of CF and transplant databases and patient charts. The Kaplan-Meier method and log-rank test were used for survival analysis and group comparison. Results From November 1991 to December 2014, 115 transplantations were performed in 106 CF patients (9 retransplantations): 3 heart-lung, 106 double lung-, 1 double lobar- and 5 single lung transplantations, constituting 13% (115/909) of all lung-transplant procedures performed in Sweden. The mean age at surgery was 31 (SD 10, range 10-61) years and there were 48% females. Overall 1-year survival after lung transplantation for CF was 86.4%, 5-year survival was 73.7% and 10-year survival was 62.4%. The mean and median survival after transplantation were 13.1 (95% confidence interval (CI): 11-15.3) and 14.6 (95% CI: 9.3-19.8) years, respectively, and there was no significant difference for gender or transplant centre. Extracorporeal membrane oxygenation was used as a bridge to transplantation in 11 cases and five patients received reconditioned lungs. Vascular and infectious complications contributed to eight deaths within the first three postoperative months. The mean survival for 14 patients infected pretransplant with Mycobacterium abscessus or Burkholderia cepacia complex was 8.8 (95% CI: 6.1-11.6) years compared to 13.2 (95% CI: 10.9-15.8) years for patients negative for these bacteria. Nineteen patients (14% of all listed), of whom three were listed for retransplantation, died while waiting a median time of 94 days (range 4 days-2.5 years) after listing. Conclusions Survival after lung transplantation in Sweden is good, also for patients with pretransplant infection with M. abscessus or B. cepacia complex, and comparable to international data.

Ultraviolet B radiation improves serum levels of vitamin D in patients with cystic fibrosis: UVB improves vitamin D in CF

Background: Ultraviolet B (UVB) radiation can be used in the prevention and treatment of vitamin D deficiency. Aim: To investigate, in a controlled study of patients with cystic fibrosis (CF), whether regular UVB radiation would improve serum levels of calcidiol during the dark season (October–April). Methods: Thirty patients with mild to moderate disease were included (aged 9–40 y). All patients had cholecalciferol supplementation. One group (15 patients) was given UVB one to three times a week for 6 mo and one group (15 sex‐ and age‐matched patients) served as controls. The radiation source consisted of three TL 12/40W UVB fluorescent lamps. Initial treatment duration was 1 min, subsequently increased by 0.5–1 min/treatment to a maximum of 10 min. Results: The mean initial serum calcidiol levels were 21 ng/ml in the controls and 22 ng/ml in the intervention group. Serum calcidiol levels increased to 44 ng/ml after 8 wk and to 50 ng/ml after 24 wk of UVB radiation; the corresponding serum levels in the controls were 19 and 25 ng/ml, respectively. The mean serum calcitriol levels increased in the treated group and were unaltered in the control group.