Pharmacokinetics of oral antimycobacterials and dosing guidance for Mycobacterium avium complex treatment in cystic fibrosis.

BACKGROUND: Treatment failure of Mycobacterium avium complex (MAC) pulmonary disease occurs in about 30% of people with cystic fibrosis (CF) and may be a result of abnormal drug concentrations. METHODS: Prospective, cross-over, single-dose PK study of 20 pancreatic insufficient individuals with CF and 10 healthy controls (HC). CF subjects received simultaneous doses of oral azithromycin, ethambutol, and rifampin in the fasting state and with food and pancreatic enzymes, separated by two weeks. HC received fasting doses only. A non-compartmental model was used to estimate PK parameters of drugs and metabolites. RESULTS: Azithromycin maximum concentration (Cmax ) was higher and rifampin Cmax was lower in fasting CF subjects compared to HC, while other PK measures, including those for ethambutol, were similar. Addition of food and enzymes did not improve the Cmax of the antimycobacterial drugs. Nineteen of 20 CF subjects had one or more abnormal Cmax z-scores in either the fasting or fed state (or both), when compared to HC. CONCLUSION: PK profiles of azithromycin and ethambutol were similar between CF and HC, except azithromycin Cmax was slightly higher in people with CF after a single dose. Rifampin PK parameters were altered in persons with CF. Addition of food and enzymes in CF subjects did not improve PK parameters. Standard dosing guidelines should be used as a starting point for people with CF initiating MAC therapy and therapeutic drug monitoring should be routinely performed to prevent the possibility of treatment failure due to abnormal drug concentrations. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02372383 Prior abstract publication: 1. Martiniano S, Wagner B, Brennan L, Wempe M, Anderson P, Nick J, Sagel S. Pharmacokinetics of oral MAC antibiotics in cystic fibrosis. Am J Resp Crit Care Med A4842-A4842, 2017. 2. Martiniano SL, Wagner BD, Brennan L, Wempe MF, Anderson PL, Nick JA, Sagel SD. Pharmacokinetics of oral MAC antibiotics in cystic fibrosis. J Cyst Fibros 16: S52-53, 2017.

Pulmonary Mycobacterium Spindle Cell Pseudotumor in Patient With Liver Transplant.

We report a case of liver transplant patient who presented with lung masses, found to be Mycobacterium spindle cell pseudotumors. The masses demonstrated hypermetabolic activities on positron emission tomography. Core biopsy revealed sheets of spindle histiocytic cells with abundant acid-fast bacilli identified as Mycobacterium avium-intracellulare complex. This finding is a rare presentation of Mycobacterium infection, mainly nontuberculous Mycobaterium. It is characterized by a benign, spindle cell mass-forming reaction. Most of the reported cases had acquired immune deficiency syndrome or organ transplant. Histopathology illustrating the proliferation of spindle cell shaped histiocytes containing numerous acid-fast bacilli is the gold standard for diagnosis. The standard treatment has not been well established; previously reported cases followed the standard treatment for Mycobacterium based on organ involvement. Our case is the first case to our knowledge that reports pulmonary Mycobacterium spindle cell pseudotumors in a liver transplant recipient.

Diagnosis of human bovine tuberculosis aided by PET/CT scanning and EBUS-TBNA.

Human bovine tuberculosis is a rare zoonotic infection in developed countries which has been achieved predominantly by effective eradication programmes in cattle. The principal modes of transmission are consumption of unpasteurised dairy products and close contact with infected cattle. The clinical and radiological presentation is indistinguishable from tuberculosis caused by Mycobacterium tuberculosis The diagnosis should be considered in individuals with relevant risk factors who present with intra/extrathoracic pathology. We describe and discuss a case of bovine tuberculosis with a synchronous primary bronchus carcinoma in an immunocompetent individual who presented with a solitary pulmonary nodule and contralateral mediastinal lymphadenopathy on CT imaging. The diagnosis of M. bovis infectionwas aided by 18F-fluorodeoxyglucose positron emission tomography/CT imaging and endobronchial ultrasound-guided mediastinal lymph node sampling.

Perianal ulcerative skin tuberculosis: A case report.

RATIONALE: Ulcerative skin tuberculosis (TB) is a rare form of extrapulmonary TB. CASE REPORT: We present a case of a 65-year-old patient with perianal ulcer, which had been present for 1 year. Anamnesis revealed he had been persistently coughing for the same period of time. Histological examination of perianal skin showed necrotizing granulomatous lesions, acid-fast staining in sputum samples was ++++, TB antibody in the blood was positive, TB DNA test was positive, and chest scan that showed secondary pulmonary TB accompanied by possible pulmonary cavity formation in the 2 upper lungs. INTERVENTIONS: Anti-TB therapy with isoniazid, rifampicin, ethambutol, and pyrazinamide for 6 months. The skin ulcer completely healed after 6 months. CONCLUSION: TB should be suspected for nonhealing ulcers. Pertinent studies should be done early during the lesion; finally, TB treatment should be initiated immediately after diagnosis is made.

Cutaneous Mycobacterium gordonae infection in an elderly diabetic returned traveller.

Mycobacterium gordonae, a low pathogenicity organism, is rarely implicated in skin and soft tissue infections. We present a 77-year-old returned diabetic traveler from rural Sudan with cutaneous M. gordonae infection. Several months of ciprofloxacin, rifampin and ethambutol led to resolution of his plaque, without signs of recurrence at 6-month follow-up.

In vitro activity of alpha-viniferin isolated from the roots of Carex humilis against Mycobacterium tuberculosis.

This study explores the antitubercular activity of α-viniferin, a bioactive phytochemical compound obtained from Carex humilis. α-Viniferin was active against both drug-susceptible and -resistant strains of Mycobacterium tuberculosis at MIC50s of 4.6 µM in culture broth medium and MIC50s of 2.3-4.6 µM inside macrophages and pneumocytes. In combination with streptomycin and ethambutol, α-viniferin exhibited an additive effect and partial synergy, respectively, against M. tuberculosis H37Rv. α-Viniferin also did not show cytotoxicity in any of the cell lines tested up to a concentration of 147 µM, which gives this compound a selectivity index of >32. Moreover, α-viniferin was active against 3 Staphylococcus species, including methicillin-susceptible Staphylococcus aureus (MSSA), methicillin-resistant Staphylococcus aureus (MRSA), and methicillin-resistant Staphylococcus epidermidis (MRSE).

In vitro antimicrobial efficacy of a fixed-dose combination of RHZE against M. tuberculosis

ABSTRACT The use of drugs in fixed-dose combination (FDC) is now recommended by the World Health Organization (WHO) due to the emergence of multidrug-resistant strains of Mycobacterium tuberculosis. FDC uses different drugs against tuberculosis (TB) in a single tablet for phase-intensive therapeutic intervention. This therapy aims to optimize treatment, to prevent inappropriate use of drugs, and to prevent the emergence of new resistant strains. This study aims to evaluate the susceptibility of clinical isolates of M. tuberculosis against rifampicin, isoniazid, ethambutol, and pyrazinamide. The antimicrobials were tested separately and in associations according to FDC. This was used for broth microdilution method, which was compared to the proportions method previously considered as the gold standard. In antimicrobials testing alone, several strains were resistant to one, two, or three drugs. However, when applied to association of drugs in FDC, there was no antimicrobial resistance. The results strengthen the FDC's concept, which aims to unite the four anti-TB drugs to combat bacterial resistance.

Tuberculous cellulitis: diseases behind cellulitislike erythema.

An 89-year-old man presented with an inflammatory erythematous plaque on the left thigh that closely mimicked cellulitis. Empiric therapies with ordinary antibiotics were not effective. A skin biopsy showed epithelioid cell granulomas throughout the dermis and subcutis. Ziehl-Neelsen stain revealed numerous acid-fast bacilli. Additionally, Mycobacterium tuberculosis was isolated from a skin biopsy specimen as well as gastric fluid and sputum cultures. He was diagnosed with tuberculous cellulitis with pulmonary tuberculosis. Cellulitis is a common disease seen by dermatologists; however, sometimes other diseases may masquerade as this banal illness. Among them, cutaneous tuberculosis should be excluded because of its clinical significance. Most cases of cutaneous tuberculosis are symptom free, but tuberculous cellulitis is sometimes painful. Therefore, cutaneous tuberculosis should always be considered in the differential diagnosis of a cellulitislike rash if the lesions do not respond to ordinary antibiotic therapy, especially in countries with a high incidence of tuberculosis.

Evaluation of crystal violet decolorization assay for minimal inhibitory concentration detection of primary antituberculosis drugs against Mycobacterium tuberculosis isolates

In this study we evaluated the crystal violet decolorization assay (CVDA) for detection of minimum inhibitory concentration (MIC) of antituberculosis drugs. 53 isolates were tested in this study and 13 of them were multidrug resistant (MDR) isolates. The antibiotics concentrations were 2-0.06 mg/L for isoniazid (INH) and rifampicin (RIF) and were 16-0.25 mg/L for streptomycin (STM) and ethambutol (EMB). Crystal violet (CV-25 mg/L) was added into the microwells on the seventh day of incubation and incubation was continued until decolorization. Decolorization of CV was the predictor of bacterial growth. Overall agreements for four drugs were detected as 98.1%, and the average time was detected as 9.5 ± 0.89 day after inoculation. One isolate for INH and two isolates for STM were determined resistant in the reference method, but susceptible by the CVDA. One isolate was susceptible to EMB by the reference method, but resistant by the CVDA. All results were concordant for RIF. This study shows that CVDA is a rapid, reliable and suitable for determination of MIC values of Mycobacterium tuberculosis. And it can be used easily especially in countries with limited-sources.

The outcomes of chemotherapy only treatment on mild spinal tuberculosis.

BACKGROUND: The treatments for spinal tuberculosis (TB) patients without absolute surgical indications have been controversial. Some people believed that most spinal TB patients were indicated for surgery, while other people believed in chemotherapy only. To help clarify the treatment over spinal TB patients without absolute surgical indications, we characterized a subtype spinal TB and then analyzed the treatment outcomes of standard chemotherapy alone. METHODS: In this retrospective study, 740 adult patients of spinal TB from January 2005 to January 2013 in our institution were reviewed. Patients who fit into the characterizations of mild spinal TB were started by standard chemotherapy for 18 months and followed up for at least 2 years upon the completion of treatment. The overall outcome, neurological function, local kyphosis, and level of pain at different time points were assessed. RESULTS: After starting the conservative treatment, 89 out of 740 patients were chosen for chemotherapy alone, and all patients were followed up for at least 2 years (ranging from 24 to 50 months) upon the completion of the treatment. Of 89 patients, 95.4 % of patients showed a definite and clinical response within 1 month after starting the treatment, 69 % of patients had excellent to good results, with no complications of the disease, and 77.5 % had asymptomatic local kyphosis with intact neurological function; solid bony fusion of adjacent segment was achieved in 88.8 % of patients. CONCLUSIONS: We believe that the mild spinal TB respond well to the standard chemotherapy, and the detailed description of mild TB would provide crucial guidance in determination of conservative treatment.

Ethambutol neutralizes lysosomes and causes lysosomal zinc accumulation.

Ethambutol is a common medicine used for the treatment of tuberculosis, which can have serious side effects, such as retinal and liver dysfunction. Although ethambutol has been reported to impair autophagic flux in rat retinal cells, the precise molecular mechanism remains unclear. Using various mammalian cell lines, we showed that ethambutol accumulated in autophagosomes and vacuolated lysosomes, with marked Zn(2+) accumulation. The enlarged lysosomes were neutralized and were infiltrated with Zn(2+) accumulations in the lysosomes, with simultaneous loss of acidification. These results suggest that EB neutralizes lysosomes leading to insufficient autophagy, implying that some of the adverse effects associated with EB in various organs may be of this mechanism.

A Breast Lump in an Elderly Lady - Carcinoma or else ?.

Breast tuberculosis (TB) is rare form of extra-pulmonary TB. It is most commonly seen in women of reproductive age group, especially in young, multiparous women who are breast feeding. In geriatric women, breast TB in some cases simulates with breast carcinoma due to common signs which include hard breast lump with nodular surface, ulceration, fixity to skin, discharging sinus, retraction of nipple, axillary lymphadenopathy etc. Hence, it is very difficult to differentiate breast TB from breast cancer, especially in elderly women on clinical ground only, and therefore, histopathological diagnosis is mandatory. Fine needle aspiration cytology is frequently inconclusive due to very small amount of tissue material, and open biopsy or lumpectomy followed by histopathological examination is necessary to confirm the diagnosis of breast TB. Six-month course of anti-tuberculous therapy - ATT (rifampicin, isoniazid, pyrazinamide and ethambutol) is adequate for complete resolution. Here, we report a case of breast TB in an elderly women presenting with left sided breast lump with ulceration of overlying skin and ipsilateral axillary lymphadenopathy. This case of tuberculous mastitis was suspected to be carcinoma due to presence of hard, tender, breast lump with irregular margin, nodular surface, ulceration, purulent discharge and ipsilateral axillary lymphadenopathy in absence of any constitutional symptoms of TB, and heterogenous, hypoechoic mass on USG, which was confirmed by histopathological examination of resected breast lump and responded fully to ATT.

Effect of SLCO1B1 Polymorphisms on Rifabutin Pharmacokinetics in African HIV-Infected Patients with Tuberculosis.

Rifabutin, used to treat HIV-infected tuberculosis, shows highly variable drug exposure, complicating dosing. Effects of SLCO1B1 polymorphisms on rifabutin pharmacokinetics were investigated in 35 African HIV-infected tuberculosis patients after multiple doses. Nonlinear mixed-effects modeling found that influential covariates for the pharmacokinetics were weight, sex, and a 30% increased bioavailability among heterozygous carriers of SLCO1B1 rs1104581 (previously associated with low rifampin concentrations). Larger studies are needed to understand the complex interactions of host genetics in HIV-infected tuberculosis patients. (This study has been registered at ClinicalTrials.gov under registration no. NCT00640887.).

Primary Gingival Tuberculosis Diagnosed Based on Genetic Identification.

A case of primary gingival tuberculosis in a 71-year-old Japanese woman is herein presented. A serous saliva culture was positive for tuberculosis, and we recognized that the origin of the tuberculosis infection was the gingiva based on the genetic identification in gingival biopsy tissue. The definitive diagnosis was facilitated by the genetic identification, a useful modern tool for diagnosing infectious diseases. The location and clinical presentation of this lesion were unusual, which underlines the importance of considering tuberculosis in the differential diagnosis of oral lesions that affect the gingiva.

Isolated hepatosplenic tuberculosis: a rare presentation.

Tuberculosis caused by Mycobacterium tuberculosis presents a major health challenge in endemic countries and spares no organ in the human body. This infection is a mimicker of various disease processes such as metastasis, lymphoproliferative diseases, and other granulomatous conditions such as sarcoidosis and fungal infections. The most challenging and important differential is metastasis, especially in the disseminated form of tuberculosis. We present a histopathologically proven case of isolated hepatosplenic tuberculosis that was provisionally diagnosed as lymphoma due to its unusual, restricted involvement of the liver and spleen.

Response to Switch from Intermittent Therapy to Daily Therapy for Refractory Nodular Bronchiectatic Mycobacterium avium Complex Lung Disease.

Intermittent three-times-weekly antibiotic therapy is recommended for the initial treatment of patients with noncavitary nodular bronchiectatic Mycobacterium avium complex lung disease. Although some experts recommend switching from intermittent to daily therapy for patients whose sputum has persistent positive cultures after intermittent therapy, the clinical efficacy of these modifications is unknown. Of 20 patients whose sputum had persistent positive cultures after 12 months of intermittent antibiotic therapy, specimens from 6 patients (30%) achieved a negative culture after a change to daily therapy.

Pulmonary mycobacterial spindle cell pseudotumor in a lung transplant patient: progression without therapy and response to therapy.

Mycobacterial spindle cell pseudotumor (MSP) represents a rare, non-malignant, mass-forming reaction to various mycobacterial infections, typically occurring in immunocompromised patients. It is characterized by the proliferation of spindle-shaped fibrohistiocytic cells without the formation of epithelioid granulomas. Without staining for acid-fast bacilli, histological distinction from other spindle cell lesions, including malignancy, can be difficult. Most of the MSP cases reported in the literature have involved lymph nodes, skin, spleen, or bone marrow, but rarely involve the lung. MSP predominately occurs in patients who are immunosuppressed. We present a patient with MSP of the transplanted lung caused by non-tuberculous mycobacteria, in whom both the natural course of the untreated pseudotumor as well as the response to antimycobacterial treatments were observed.

Meningoencefalitis tuberculosa post primaria / Tuberculous meningoencephalitis post primary

La tuberculosis continúa siendo una enfermedad prevalente en Bolivia, la cual tiene problemas serios en el diagnóstico de sus formas extra pulmonares con pocos datos sobre la eficacia del tratamiento en muchos de estos escenarios. La tuberculosis meníngea es una de las formas de presentación que ofrece mayores problemas al momento de establecer el diagnóstico, qué a pesar de contar con el tratamiento específico representa aún una importante morbilidad y mortalidad. Se presenta el caso de una mujer de 31 años con síntomas neurológicos de curso agudo, con antecedente de contacto previo con la enfermedad por medio de un familiar a tuberculosis. Se describirá el curso clínico, laboratorial, imagenológico y los hallazgos en líquido cefalorraquídeo. Además de una revisión de la literatura sobre el diagnóstico y tratamiento de esta entidad.

Tuberculosis continues being one prevalent disease in Bolivia, which has serious problems in the diagnosis of extra-pulmonary forms with very few data on the effectiveness in treatment. Meningeal tuberculosis is one of the tuberculosis forms with biggest problems when establishing the diagnosis, with significant morbidity and mortality despite specific treatment. In this report, a case of meningeal tuberculosis is exposed in a 31 year old woman with acute onset of neurological symptoms, with a history prior contact with the disease. It's described a clinical laboratory, imagenology and findings in liquid In addition, a review of the literature aspect to the diagnosis and treatment of the entity.