Extensive Cutaneous Botryomycosis With Subsequent Development of Nocardia-Positive Wound Cultures.

Botryomycosis is a rare, chronic granulomatous infection caused by a response to bacteria, most commonly Staphylococcus aureus. Cutaneous manifestations, such as subcutaneous nodules, nonhealing ulcers, or sinus tracks, typically occur following inoculation of bacteria after trauma. Drainage from the skin lesions may contain yellow grains resembling those seen in actinomycosis and nocardiosis. A 20-year-old Hispanic male presented over the course of several years with a chronic nonhealing left posterior scalp wound. A car hit the patient when he was 2 years old and injured the scalp in the location of the skin lesion. Multiple wound cultures grew methicillin-resistant Staphylococcus aureus (MRSA), and biopsies were consistent with botryomycosis. He was treated with multiple surgical debridements, skin grafts, and various courses of oral and intravenous antibiotics with slight improvement. One reason for poor response to therapy was noncompliance with long-term home antibiotics. The most recent tissue culture grew MRSA in addition to Nocardia mexicana, and he experienced improvement on linezolid and minocycline. Although it is important to exclude nocardiosis and actinomycosis when diagnosing botryomycosis, our patient was diagnosed with botryomycosis after multiple biopsies and positive MRSA cultures 2 years prior to 1 positive N mexicana culture. Our case is a unique presentation of botryomycosis in an individual who subsequently developed Nocardia-positive wound cultures.

Extensive mycetoma in forearm, chest and neck due to Nocardia mexicana.

INTRODUCTION: Mycetoma is a chronic granulomatous inflammatory disease of the subcutaneous tissue, which affects deep structures and bone. Most cases of actinomycetoma are caused by members of the genus Nocardia. CASE PRESENTATION: Here we report the case of a 43-year-old male who presented a disseminated mycetoma on the forearm, chest and neck, characterized by enlarged and erythematous lesions through which seropurulent material drains, and numerous atrophic scars. Molecular identification was performed by 16S gene amplification and sequencing. Nocardia mexicana was identified with 100% identity. Trimethoprim-sulfamethoxazole, diaminodiphenyl sulfone and amikacin was a successful treatment after 6 months. CONCLUSIONS: Nocardia mexicana is a rare organism that causes mycetoma. We report a case of extensive mycetoma on the forearm with spread to the neck and thorax associated with manipulation of the mouth of a calf.

Treatment of refractory localized pulmonary nocardiosis caused by Nocardia mexicana with a combination of medication and surgery.

Pulmonary nocardiosis is a rare disease that is often difficult to cure because of its tendency to recur. Here, we report a case of refractory localized pulmonary nocardiosis caused by Nocardia mexicana. A 60-year-old Japanese woman had recurring pulmonary nocardiosis four times previously and each time she was treated with antibiotics for a sufficient duration; nevertheless, the disease continued to recur, probably because of resistance to antibiotics. As a fifth treatment, we performed middle lobe resection and pre- and post-operative antimicrobial therapy for 6 months. The combination of medication and surgery was useful for treating refractory localized pulmonary nocardiosis.

First case report of pulmonary and cutaneous nocardiosis caused by Nocardia mexicana in Iran.

BACKGROUND: Nocardia are aerobic partially acid-fast bacteria that are environmentally ubiquitous. This group of bacteria causes a rare bacterial infection of either the lungs (pulmonary) or body (systemic) that usually affects immunocompromised individuals. Nocardia mexicana was first isolated in 2004 from a patient with chronic bronchitis. However, there have been few reports on the clinical significance of this organism up to now. We herein report the first cases of N. mexicana in patients with pulmonary and cutaneous infection from Iran. CASE PRESENTATION: A 57-year-old man was admitted to hospital due to a cutaneous wound on his left foot, fever, weakness, persistent cough and chest pain. At first, due to clinical examination and laboratory test, the patient was diagnosed as having tuberculosis. However, PCR of Mycobacterium tuberculosis was negative from broncho-alveolar lavage (BAL) samples. Direct PCR of BAL was performed for this patient and according to the clinical examinations and microbiological evaluations; the micro-organism was identified as N. mexicana and was isolated from both BAL and the wound. Finally, the patient was treated with linezolid and amikacin. CONCLUSION: The infections, with actinomycetes such as Nocardia , are easily neglected or misdiagnosed due to the fastidious nature of the organism and the inadequate microbiological experience of laboratories in the hospitals of developing countries. This case shows that hospitals should consider a better laboratory protocol to deal with the clinical cases in which fastidious organisms, and in particular Nocardia , are involved.

First case report of pulmonary nocardiosis caused by Nocardia mexicana.

INTRODUCTION: Nocardia species usually cause opportunistic infections, and the frequency of these infections is increasing owing to the growing population of immunocompromised hosts. However, Nocardia species may sometimes cause an infection disease in immunocompetent hosts. Nocardia mexicana infections are the least common and are very rare. CASE PRESENTATION: Herein, we report the first case of a pulmonary infection with N. mexicana in a 61-year-old Japanese woman with a history of hyperlipidaemia and bronchiectasis and a 6-month history of non-productive hacking cough. A sample of bronchial lavage fluid obtained by bronchofiberscopy showed filamentous branching gram-positive rods and acid-fast filamentous branching rods, and a colony of suspected Nocardia was cultured. Based on 16S rRNA, gyrB,rpoB, secA1 and hsp65 gene sequence analyses and biochemical and physiological properties, the strain was identified as N. mexicana. The strain was resistant to the antimicrobial agents amoxicillin-clavulanic acid, clarithromycin, minocycline, gentamycin, tobramycin, ciprofloxacin and trimethoprim-sulfamethoxazole. The patient was treated with biapenem followed by intravenous amikacin and oral linezolid. CONCLUSION: Despite its rarity, the species require attention owing to the existence of multidrug-resistant strains.

Isolation of Nocardia mexicana from focal proliferative tenosynovitis and arthritis in a steer.

CASE REPORT: An 18-month-old Charolais steer was presented with lameness and fluctuant swelling of the right stifle joint, which yielded neutrophils on fine-needle aspiration. A diagnosis of bacterial proliferative tenosynovitis and arthritis was made on postmortem and histological examination. Culture and 16S rRNA sequencing identified a Nocardia sp. with 99% homology with the corresponding DNA fragment of N. mexicana DSM 44952. Antimicrobial susceptibility testing revealed the isolate was susceptible to co-trimoxazole and third-generation cephalosporins. CONCLUSION: We report the first case, both in Australia and internationally, of proliferative tenosynovitis and arthritis caused by Nocardia spp. infection in a bovine and the first report of pathology attributed to N. mexicana in a veterinary patient. Given the limited susceptibility of the bacteria, the poor antimicrobial penetration that would be expected and the morphological changes that had taken place in the joint; the steer would have required protracted antimicrobial treatment in addition to invasive debridement of the lesion. This case emphasises the importance of routinely performing cytology and extended incubation of cultures in cases of arthritis in order to make ethical and economically viable treatment decisions.