Mycobacterioses Induced by Mycobacterium abscessus: Case Studies Indicating the Importance of Molecular Analysis for the Identification of Antibiotic Resistance.

Mycobacterioses are less frequently occurring but serious diseases. In recent years, at a global level, the incidence of mycobacterioses induced by the rapidly growing species Mycobacterium abscessus (M. a.), which is considered to be the most resistant to antibiotics and most difficult to treat, has been on the rise. Correct identification to the level of the subspecies (M. a. abscessus, M. a. massiliense, and M. a. bolletii) and determination of its sensitivity to macrolides, which are the basis of combination therapy, are of principal importance for the management of the disease. We describe five cases of mycobacterioses caused by M. a., where the sequencing of select genes was performed to identify the individual subspecies and antibiotic resistance. The analysis of the rpoB gene showed two isolates each of M. a. abscessus and M. a. massiliense and one isolate of M. a. bolletii. The complete (full length) erm(41) gene responsible for the development of inducible resistance to macrolides was demonstrated in both M. a. abscessus and M. a. bolletii isolates. A partially deleted and non-functional erm(41) gene was demonstrated in M. a. massiliense isolates. The subsequent sequencing of the full length erm(41) gene products showed, however, the mutation (T28→C) in both isolates of M. a. abscessus, causing a loss of the function and preserved sensitivity to macrolides. The antibiotic sensitivity testing confirmed that both the isolates of M. a. abscessus and M. a. massiliense were sensitive to clarithromycin even after prolonged 14-day incubation. The inducible resistance to clarithromycin was maintained only in M. a. bolletii. Thus, the sequence analysis of the erm(41) gene can reliably identify the preservation of sensitivity to macrolides and serve as an important tool in the establishment of therapeutic regimens in cases of infections with M. abscessus.

Transjugular intrahepatic portosystemic shunt in five children with cystic fibrosis: long-term results.

BACKGROUND/AIMS: The aim of this study was to report results of TIPS (transjugular intrahepatic portosystemic shunt) in 5 consecutive children with cystic fibrosis and monitor long-term follow-up results. METHODOLOGY: Five cystic fibrosis patients with multinodular cirrhosis of the liver and complications of portal hypertension (repeated variceal bleeding refractory to endoscopic treatment) underwent TIPS creation. There were 3 males and 2 females aged 8 to 18 years (median 14 yrs), their weight range was 27-51 (median 40) kg. A routine TIPS technique was used. The patients were followed by ultrasonography. RESULTS: The TIPS was successfully performed in all five patients. The mean portosystemic pressure gradient was reduced from 17 to 10 mmHg. There were no deaths related to the procedure. No clinical or laboratory signs of bleeding into the gastrointestinal tract were observed in any patient within the first 30 days following TIPS. There was recurrent bleeding 6 times and asymptomatic stenoses were revealed by ultrasonography 15 times during a follow-up period of 15-81 (median 70) months. All stenoses were successfully dilated. One patient had liver transplantation 15 months after TIPS. Two patients died 6.7 years and 4.5 years following the placement of TIPS due to respiratory insufficiency. CONCLUSIONS: Symptomatic portal hypertension was successfully managed with TIPS in long-term follow-up; multiple reinterventions were required for shunt stenoses. TIPS served as a bridge to liver transplantation in one case.