Disseminated Mycobacterium celatum infection in a white-tailed trogon (Trogon viridis)

A rare case of pulmonary mycobacteriosis caused by rifabutin resistant Mycobacterium celatum and review of the literature

The present case demonstrates an atypical pulmonary mycobacteriosis that mimicked classical symptoms and radiology findings for tuberculosis. While T-SPOT Test and PCR analyses proved negative for tuberculosis, microscopic sputum evaluation showed acid-fast bacilli and Mycobacterium celatum was found in culture. Uniquely, in our case M. celatum was resistant to rifabutin. Therefore, after not responding to combination treatment including rifabutin, our patient was treated with ethambutol, clarithromycin and protionamide. Classical risk factors for atypical mycobacteriosis such as immunodeficiency (including medication-induced), preexisting pulmonary disease or multimorbidity were not present. We conclude that the high age of the patient (92 y) may have been the main contributing factor for the infection.

TB or not TB? Mycobacterium celatum mimicking Mycobacterium tuberculosis: A case of mistaken identity

Mycobacterium celatum is a slow-growing, non-tuberculous mycobacterium (NTM) and a rare cause of infection in humans. Infection occurs primarily by inhalation or direct inoculation from environmental sources, and this pathogen has been reported to cause localized infections in the lungs and lymph nodes of both immunocompetent and immunocompromised patients, and disseminated disease in immunocompromised patients. Here, we present a case of pulmonary infection with M. celatum in an immunocompetent 68-year-old male with clinical features similar to tuberculosis. The patient initially developed palpitations, worsening fatigue, night sweats, dyspnea, productive cough, and weight loss. Computed tomography angiogram of the chest revealed a right upper lobe pulmonary artery embolus and extensive biapical fibronodular cavitary densities. Two separate sputum samples were positive for acid-fast bacilli (AFB) and sputum cultures were positive for M. celatum. The patient responded well to treatment with clarithromycin, ciprofloxacin, and ethambutol. We advise physicians to consider M. celatum infection in the differential diagnosis of patients with symptoms and radiographic and microbiologic evidence suggestive of NTM pulmonary infection.

Evaluation of Multidrug Therapy With Azithromycin, Rifampin, and Ethambutol for the Treatment of Mycobacterium avium subsp avium in Ring-neck Doves (Streptopelia risoria): An Uncontrolled Clinical Study

An uncontrolled clinical study was conducted to evaluate the efficacy of a multidrug protocol in 16 ring-neck doves ( Streptopelia risoria ) from a flock naturally infected with Mycobacterium avium subsp avium. The doves were considered infected on the basis of a high prevalence of infection in a group of 29 birds that were euthanatized from the same flock and clinical signs and pathologic results consistent with infection in the remaining birds. All birds were treated with azithromycin (43 mg/kg), rifampin (45 mg/kg), and ethambutol (30 mg/kg) administered orally once daily for 180 days. Five birds died during treatment and were confirmed positive for mycobacteriosis on postmortem examination. Of the remaining 11 birds, infection and disease were present in 9 (81.8%) at the end of the treatment. Postmortem investigation showed that 2 mycobacterial isolates were resistant to ethambutol, intermediately sensitive to rifampin, and sensitive to azithromycin. Microscopic examination of liver sections equivalent of those that would be taken for biopsy showed that biopsy as a method of monitoring birds for treatment success had poor sensitivity. Toxicity associated with drug therapy was not observed in these doves nor in 6 outwardly healthy ring-neck doves exposed to the same treatment. The results of this study showed that this protocol of azithromycin, rifampin, and ethambutol has poor efficacy when administered for 180 days for treatment of doves infected with M avium subsp avium.

Effect of long-term freezing and freeze-thaw cycles on indigenous and inoculated microorganisms in dewatered blackwater

Wastewater treatment in many Arctic regions is inadequate, even nonexisting. Natural freezing of wastewater in those areas may be beneficial for reduction of microorganisms. The aim of this study was to investigate the effect of long-term freezing, and repeated freezing and thawing, on indigenous coliforms, fecal streptococci, and antibiotic-resistant (AR) bacteria, and inoculated Salmonella Enteriditis and E. coli bacteriophage ΦX174 in dewatered blackwater. At the end of the long-term freezing experiment (10 months), an MPN recovery study was done, including the microbial groups that had shown the largest reduction, using tryptone soy broth at incubation temperatures of 10 and 20 °C overnight for the coliforms and AR bacteria, and buffered peptone water at incubation temperature of 37 °C for 18-20 h for Salmonella. Fecal streptococci were more resistant to long-term freezing than the coliform group. Total number of AR bacteria decreased slowly but constantly over the 10-month freezing period. Salmonella rapidly decreased and were nondetectable within a week but exhibited some recovery after 10 months of freezing, whereas limited or no recovery of coliforms and AR-bacteria was detected. Bacteriophages showed limited reduction during the long-term freezing. Repeated freezing and thawing increased the reduction of all tested microbial groups markedly.

Pathology of mycobacteriosis in birds

Avian mycobacteriosis is a disease that affects companion, captive exotic, wild, and domestic birds. The disease in birds is generally caused by Mycobacterium avium subsp avium but more than 10 other species of mycobacteria infect birds. Oral route of infection appears to be the primary mode of transmission. In some cases, the extensive involvement of the respiratory system suggests an airborne mode of transmission. Molecular diagnostic techniques have improved the ability to confirm the disease. Avian mycobacteriosis is an important veterinary and economic risk in birds and mammals. Exposure of humans to infected birds may cause a zoonotic infection.

The First Report of Mycobacterium celatum Isolation from Domestic Pig (Sus scrofa domestica) and Roe Deer (Capreolus capreolus) and an Overview of Human Infections in Slovenia

Mycobacterium celatum, a slowly growing potentially pathogenic mycobacterium first described in humans, is regarded as an uncommon cause of human infection, though capable of inducing invasive disease in immunocompromised hosts. According to some reports, a serious disease due to M. celatum may also occur in individuals with no apparent immunodeficiency. In animals, an M. celatum-related disease has been described in three cases only: twice in a domestic ferret (Mustela putorius furo) and once in a white-tailed trogon (Trogon viridis). In this paper, we report the first detection of M. celatum in a domestic pig (Sus scrofa domestica) and roe deer (Capreolus capreolus). A nation-wide overview of human M. celatum infections recorded in Slovenia between 2000 and 2010 is also given. Pulmonary disease due to M. celatum was recognized in one patient with a history of a preexisting lung disease.

Disseminated mycobacteriosis in a bald eagle (Haliaeetus leucocephalus)

A mature bald eagle (Haliaeetus leucocephalus) was diagnosed with mycobacterial infection after being presented for an inability to fly, emaciation, and a swelling of the left tibiotarsal-tarso metatarsal joint. Results of a complete blood cell count revealed a persistent, marked leukocytosis, with heterophilia, monocytosis, and anemia. Radiographs revealed lysis of the left distal tibiotarsus and soft-tissue swelling around the left tibiotarsal-tarsometatarsal joint, multiple pulmonary opacities, and an enlarged liver. Endoscopic evaluation and biopsy of caseated material within the left caudal coelom revealed acid-fast organisms. The eagle was euthanatized, and results of necropsy and histologic evaluation revealed caseated granulomas of the intestine, lungs, air sacs, and subcutaneous regions of the hock. Results of culture, a polymerase chain reaction testing, and direct deoxyribonucleic acid (DNA) sequencing for mycobacterial 16S ribosomal ribonucleic acid DNA determined this organism most likely to be Mycobacterium avium.