An unusual presentation of primary cutaneous nocardiosis at a rare site: succesful treatment with a modified Welsh regimen

INTRODUCTION

Primary cutaneous nocardiosis can present in various forms. Clinically, it can present as acute infection (abscess or cellulitis), mycetoma, or sporotrichoid infection. Mycetoma over the back is rare.

CASE REPORT

We herein describe a case of primary cutaneous nocardiosis presenting as a mycetoma, caused by Nocardia brasiliensis. The patient had extensive lesions over the back, which can be attributed to the fact that the patient, being an agriculturist, has been exposed to recurrent trauma while carrying firewood and soiled sacks. He responded well to a modified Welsh regimen. Initially, within 2 cycles, the patient showed dramatic improvement clinically, wherein the sinuses, granulation tissue, and induration were no longer apparent. However, the patient showed a small discharging sinus at the end of 3rd pulse, so a total of 6 cycles were given. An additional 2 months of maintenance phase treatment with cotrimoxazole and rifampicin were given. On follow-up, the patient showed no recurrence at 6 months.

CONCLUSION

We report a case of primary cutaneous nocardiosis presenting as a mycetoma on the back. Enlisting the help of a microbiologist allowed us to isolate the causative organism. Early recognition and prompt treatment prevents unwarranted surgical debridement and complications.

[Two cases of Nocardia farcinica brain abscess]

Brain abscess caused by Nocardia is a relatively rare disease, but its prognosis is poor, with the fatality being 3 times as high as that of other types of brain abscess. Nocardiosis caused by N. farcinica has higher fatality rates than nocardiosis caused by the other bacteria of the genus Nocardia. We report two cases of brain abscess caused by N. farcinica. Case 1: 72-year-old immunocompetent man. In this case, the disease healed in response to burr hole drainage and treatment with antibiotics (pazufloxacin, ciprofloxacin). Case 2: A 78-year-old woman with a history of liver cirrhosis. This patient received burr hole drainage and treatment with multiple antibiotics (sulfamethoxazole/trimethoprim, pazufloxacin, meropenem, amikacin, minocycline, and linezolid). Her brain abscess tended to alleviate but her general condition worsened, leading to death. N. farcinica is often resistant to multiple antibiotics. For treatment of brain abscess caused by this bacterium, it is essential to perform pathogen identification and a drug sensitivity test immediately, and to select optimum antibiotics, taking into account the general condition of individual patients.

[Microbiological and clinical features of nine cases with nocardial infections]

Following recent advance in medical technology, the increase of immunocompromised patients results in an increase of opportunistic infections such as nocardiosis. However, little is known about relationships between clinical features of nocardial infections and each Nocardia species, especially newly identified ones. Therefore, we identified clinical isolates of Nocardia species by genetic methods and analyzed clinical features of nocardiosis. Nine clinical isolates were obtained in Kyushu University Hospital from 2005 to 2008. Six different Nocardia species were identified by 16Sr RNA: Nocardiafarcinia (n=2), Nocardia brasiliensis (n=2), Nocardia cyriacigeorgica (n=2), Nocardia transvalensis (n=1), Nocardia araoensis (n=1) and Nocardia testacea (n=1). The underlying diseases of 9 patients were pulmonary diseases(n=5), malignant diseases(n=3), collagen diseases(n=1) or primary immunodeficiency diseases (n=l). According to antimicrobial susceptibility testing, none of them was resistant to minocycline or linezolid. Among seven isolates from respiratory specimens, one was resistant to imipenem, sulfamethoxazole/trimethoprim and amikacin, two were to ciprofloxacin. Three species identified recently (N cyriacigeorgica, N. araoensis and N. testacea) were involved in this study and most of them were considered as infectious pathogens to human. These data suggested the identification of Nocardia to the species level and susceptibility testing were important for diagnosis as infectious diseases and treatments.

The first case of catheter-related bloodstream infection caused by Nocardia farcinica

Nocardia farcinica is an emerging pathogen in immunocompromised hosts. Even though several species of Nocardia have been reported as causative pathogens of catheter-related blood stream infections (CRBSI), CRBSI caused by N. farcinica has not been reported. A 70-yr-old man with a tunneled central venous catheter (CVC) for home parenteral nutrition was admitted with fever for two days. Norcardia species was isolated from the blood through CVC and peripheral bloods and identified to N. farcinica by 16S rRNA and rpoB gene sequence analyses. This report emphasizes the rapid and correct identification of causative agents in infectious diseases in the selection of antimicrobial agents and the consideration of catheter removal.

Identification of acid-fast bacilli using pyrosequencing analysis

Pyrosequence identification of 117 isolates of acid-fast bacilli (AFB) was compared to both routine phenotypic methods and Sanger sequencing. Two (2) vendor-provided pyrosequencing primers specific for AFB were used for the study. Pyrosequence analysis correctly identified 114 (98%) of the tested 117 AFB isolates. Among the test Mycobacterium spp., 18 of 20 Mycobacterium spp. were identified correctly to the species level. All rapidly growing mycobacteria were correctly identified to species by pyrosequencing. Other slowly growing mycobacteria such as Mycobacterium tuberculosis, Mycobacterium kansasii, Mycobacterium avium-intracellulare, and others were easily identified by pyrosequencing. Only Mycobacterium simiae and Mycobacterium scrofulaceum were not identifiable by the pyrosequence method. Among the 25 Nocardia isolates, all were correctly identified to the genus level. Identification of AFB by pyrosequence analysis provides both a rapid and accurate method for this group of organisms.

Bacteria with dual resistance to elevated concentrations of heavy metals and antibiotics in Nigerian contaminated systems

Samples of soil, water, and sediments from industrial estates in Lagos were collected and analyzed for heavy metals and physicochemical composition. Bacteria that are resistant to elevated concentrations of metals (Cd(2+), Co(2+), Ni(2+), Cr(6+), and Hg(2+)) were isolated from the samples, and they were further screened for antibiotic sensitivity. The minimum tolerance concentrations (MTCs) of the isolates with dual resistance to the metals were determined. The physicochemistry of all the samples indicated were heavily polluted. Twenty-two of the 270 bacterial strains isolated showed dual resistances to antibiotics and heavy metals. The MTCs of isolates to the metals were 14 mM for Cd(2+), 15 mM for Co(2+) and Ni(2+), 17 mM for Cr(6+), and 10 mM for Hg(2+). Five strains (Pseudomonas aeruginosa, Actinomyces turicensis, Acinetobacter junni, Nocardia sp., and Micrococcus sp.) resisted all the 18 antibiotics tested. Whereas Rhodococcus sp. and Micrococcus sp. resisted 15 mM Ni(2+), P. aeruginosa resisted 10 mM Co(2+). To our knowledge, there has not been any report of bacterial strains resisting such high doses of metals coupled with wide range of antibiotics. Therefore, dual expressions of antibiotics and heavy-metal resistance make the isolates, potential seeds for decommissioning of sites polluted with industrial effluents rich in heavy metals, since the bacteria will be able to withstand in situ antibiosis that may prevail in such ecosystems.

Nocardiosis dissemination following transthoracic needle biopsy: two case reports

Pulmonary nocardiosis is a rare respiratory infection whose diagnosis can easily be missed because there are no suggestive symptoms. Nocardiosis is typically regarded as an opportunistic infection, but one-third of infected patients are immunocompetent. We present two situations of pulmonary lesions in immunocompetent people. A CT-guided percutaneous transthoracic needle biopsy was performed in both cases but was not informative. Suppurative inflammation had developed as a complication of the procedure in the biopsy site after 1-2 weeks. Pus was aspirated and culture showed Nocardia spp. Therefore we hypothesize that the pulmonary lesion was caused initially by Nocardia which had subsequently disseminated to the chest wall after the biopsy. Treatment with trimethoprim/sulfamethoxazole was undertaken. Resolution of the disease was evaluated according to the clinical symptoms and radiological resolution after 6 months therapy.

Disseminated nocardiosis in an advanced AIDS patient

Nocardiosis is often misdiagnosed as tuberculosis in patients with HIV, as both diseases have similar manifestations. We describe the successful management of a case of advanced AIDS with disseminated Nocardial infection due to N. asteroides. Nocardial infection needs to be suspected in a patient with HIV infection when there is chest radiographic abnormality and when thrice sputum microscopy for acid fast bacilli is negative.

[Subcutaneous abscess due to Nocardia farcinica]

An 64-year-old-woman with hypersensitivity pneumonia treated with combined of prednisolone and sulfamethoxazole and trimethoprim had a history of infectious pneumonia due to an unknown pathogen. About two weeks before she was first seen, she noticed right back swelling increasing rapidly in size and pain. Incision of the skin lesion produced a massive amount of pus and a pus smear showed acid-fast gram-positive branching filaments confirming diagnosis of nocardiosis. Symptoms decreased following open drainage and intravenous ceftriaxone and amikacin administration, but the woman died of urinary tract infection three months after diagnosis. Organisms isolated from pus were identified as Nocardia farcinica, thought to have infiltrated secondary from a pulmonary lesion to subcutaneous abcesses.

Pulmonary nocardiosis due to Nocardia farcinica in a renal transplant recipient

Nocardia farcinica is an infrequent cause of nocardiosis among the renal transplant recipients and it has not been reported so far from India. We report a case of pulmonary nocardiosis due to N. farcinica in a 32-year-old woman with hypothyroidism and post-renal transplant status, currently on immunosuppressive therapy (prednisolone, azathioprine and tacrolimus). The N. farcinica isolate was susceptible to trimethoprim-sulfamethoxazole (TMP-SMZ), linezolid, imipenem, gentamicin but resistant to ceftriaxone, ciprofloxacin, tobramycin, erythromycin, amoxycillin-clavulanic acid and tetracycline. Treatment with TMP-SMZ and linezolid resulted in marked clinico-radiological improvement but after two weeks both of the drugs had to be stopped due to severe pancytopenia as adverse effect of their use. Currently, the patient is on imipenem and remains stable after four weeks of treatment. In N. farcinica infections, multi antibiotic resistance and toxicity of some specific drugs enhances the risk of therapeutic failure in renal transplant recipients.

[Nocardia aroensis and lung infection: first case report in Africa ]

Nocardiosis is a rare disease that is difficult to diagnose. Pulmonary forms are most common in association with a variety of nonspecific symptoms. Up to now isolation of the offending species, i.e., Nocardia aroensis, has been reported only once during the first description in Japan. The purpose of this article is to report the second world case of isolation of the Nocardia aroensis in a 50-year-old immunocompetent African woman.

Subretinal Abscess Due toNocardia farcinicaResistant to Trimethoprim- Sulfamethoxazole in a Patient with Systemic Lupus Erythematosus

PURPOSE

To report a case of subretinal abscess due to Nocardia farcinica resistant to trimethoprim-sulfamethoxazole in a patient with systemic lupus erythematosus on immunosuppressive therapy.

DESIGN

Observational case report.

METHODS

We retrospectively studied the medical record of a patient with nocardiosis.

RESULTS

The microorganism disseminated from the lungs (pneumonia) to the eye and brain. The ocular lesion appeared to be a yellowish, lobulated subretinal abscess with irregular surface and superficial retinal hemorrhages. As it was not responding to empiric therapy for nocardia, pars plana vitrectomy and aspiration of the subretinal material was performed to confirm the etiology.

CONCLUSION

In an immunocompromised patient with pulmonary involvement and a subretinal abscess with a characteristic aspect, one should consider nocardia as a possible etiology taking into account its possible antibiotic resistances.

Nocardia farcinicabrain abscess in a patient without immunocompromise

Brain abscess has an incidence of 1 per 100,000 in developed countries and a mortality rate of 10%. Cerebral infections with Nocardia farcinica have a mortality of up to 90%. Nocardial species are important pathogens in immunocompromised hosts, but infections in immunocompetent patients are extremely rare. We report a case of primary brain abscess with N. farcinica in a patient without immunosuppression, which was treated with surgery and a one-year course of oral moxifloxacin.

[A case of pulmonary nocardiosis with simultaneous identification of N. farcinica and N. cyriacigeorgica]

A 51-year-old man with bronchiectasis and persistent lower respiratory tract infection was referred to our hospital for further evaluation of a mass shadow in the upper lung field on his chest X-ray film in February 2006. Two Nocardia spp (N. cyriacigeorgica and N. farcinica) were simultaneously identified from sputum collected through bronchoscopy by culture. We diagnosed pulmonary nocardiosis and commenced minocycline treatment. The possibility of lung cancer was excluded by sputum cytology and CT guided lung biopsy. Remarkable improvement of the mass lesion was recognized after treatment for 6 months. To the best of our knowledge, double infection of two species of Nocardia is very rare.

Isolation and properties of a 2-chlorovinylarsonic acid-degrading microorganism

2-Chlorovinylarsonic acid (CVAOA) is a stable abiotic metabolite of lewisite 1 that has been identified in lewisite dumps. There have been no reports of microbial degradation of CVAOA, so we isolated and examined CVAOA-degrading microorganisms. CVAOA contains arsine, which is toxic to microbial growth. We therefore used the simple organic chemical, ethylene, as a sole carbon source in initial screening for suitable microbes. We isolated several microorganisms from sewage sludge and soil. Two strains, NK0505 and NK0506, could be grown on CVAOA as the sole carbon source and were identified by 16S rRNA sequencing as Nocardia carnea NK0505 and Rhodococcus opacus NK0506. Because N. carnea NK0505 was slightly more active in degrading CVAOA, we used it for further degradation studies. Strain NK0505 utilized about 90% of CVAOA (50 ppm) within 5 days; at higher concentrations of CVAOA no degradation occurred over a 10-day period. We identified 1-chloro-1,2-dihydroxyethane, ethylene glycol, glycolic acid, and arsenic acid as degradation products of CVAOA. Epoxy formation on alkylarsine was not confirmed. CVAOA is probably further metabolized via these compounds in the tricarboxylic acid cycle. Strain NK0505 could also degrade but-3-enylarsonic acid, trichloroethylene, isoprene, and 1,3-butadiene, but utilization of tetrachloroethylene and acetylene did not occur.

[Nocardiosis]

Nocardia is a rare, but serious cause of infection in immunosuppressed patients. Pulmonal nocardiosis is the most frequent manifestation. The ability of Nocardia to disseminate haematogenously frequently causes infection in other organs and increases mortality. We present two cases caused by Nocardia: a patient with a cerebral abscess and a patient with bacteremia. The use of 16S rDNA sequencing for identification reduces the time spent on the final diagnosis, why relevant treatment can be initiated early which improves the prognosis.

Nocardia seriolae infection in the three striped tigerfish, Terapon jarbua (Forsskål)

An epizootic in pond cultured three striped tigerfish, Terapon jarbua, in Taiwan was caused by Nocardia seriolae. Diseased fish first showed clinical signs and mortalities in February and March 2003. The cumulative mortality within 2 months was 2.4% (1200 of 50 000) and affected fish were 7 months old with total lengths from 18 to 25 cm. Most affected fish were pale and lethargic with haemorrhages and ulcers on the skin. The most significant gross pathological changes were varying degrees of ascites and enlargement of the spleen, kidney and liver. Obvious white nodules, varying in size, were found in these organs. Bacteria were either coccal or filamentous in appearance, with bead-like forms. Isolates from diseased fish were characterized using the API ZYM (Analytical profile index; Bio Mérieux, France) systems and conventional tests and identified as Nocardia sp. The isolate was designated NS127 and was confirmed as N. seriolae by a polymerase chain reaction assay that gave the expected specific 432 bp amplicon. In addition, its 16S rDNA sequence gave 100% sequence identity with N. seriolae. A partial sequence of the 16S rRNA gene, heat shock protein gene and RNA polymerase gene (rpo B) of NS127 and the type strain of N. seriolae BCRC 13745 formed a monophyletic clade with a high sequence similarity and bootstrap value of 99.9%. White nodules induced in experimental fish were similar to naturally infected cases and N. seriolae was re-isolated on brain heart infusion agar. This is the first report of N. seriolae-infection in three striped tigerfish in aquaculture.

Antimicrobial activity screening of some sulfonamide derivatives on some Nocardia species and isolates

Nocardia are aerobic, catalase-positive, Gram-positive microorganisms and typically acid-alcohol fast at some stage of the growth cycle. The genus Nocardia, a member of Mycolata group, is clinically important because it is an opportunistic pathogen. The sulfonamide derivative medicines are prefered to cure infection caused by Nocardia, such as nocardiaosis and mycetoma. Antimicrobial activities of seven sulfonamide derivatives have been investigated against some Nocardia species and isolates using the disk diffusion method on Sensitest agar medium (Oxoid). Thirty-six organisms, which consisted of 10 soil isolates selected from different clusters of Aymen study (2003), six clinical isolates provided by Ege University, Medical School, Microbiology and Clinical Microbiology Department, four reference strains, 15 type strains and a control strain of Staphylococcus aureus ATCC 43300 were tested. The strongest inhibition was observed in the cases of IV [N-(2-hydroxy-4-nitro-phenyl)-4-methyl-benzensulfonamid], V [N-(2-hydroxy-5-nitro-phenyl)-4-methyl-benzensulfonamid] and III [N-(2-Hydroxy-phenyl)-4-methyl-benzenesulfonamide] against Nocardia. Introducing a hydroxyl group into the ortho position on the ring increased the antimicrobial activity. Substitution of the electron withdrawing groups such as a nitro group increased the antimicrobial activity remarkably.

A case of disseminated Nocardia farcinica diagnosed through DNA sequencing in a kidney transplantation patient

Nocardia is a rare gram-positive bacteria causing opportunistic infection, and belongs to the aerobic Actinomycetes group. As the mortality in the immunocompromised patients with nocardiosis is high, early diagnosis and treatment is very important. However, clinical manifestations of infection caused by Nocardia are very variable and early diagnosis is limited by the difficulty in obtaining specimens and its isolation. Rapid diagnosis of Nocardia infection may allow for earlier effective therapy, thus improving patient outcome. We report a case of Nocardia farcinica diagnosed by DNA sequencing through blood culture in a renal transplant recipient with severe pneumonia and multiple brain abscesses.

Actinomycetoma by Nocardia brasiliensis in a girl with Down syndrome

We describe the case of a 14-year-old girl with Down syndrome and a large cutaneous plaque localized to the right neck and shoulder that had enlarged over five years after a minor traumatic injury. The plaque was characterized by numerous inflammatory nodules and fistulae that secreted purulent discharge. Nocardia grains were identified and Nocardia brasiliensis was identified by culture. Histopathology examination showed a chronic inflammatory infiltrate with granuloma development. The treatment scheme was with Diaminodiphenylsulfone 50/mg/d and Trimethoprim-Sulfamethoxazole 800/160 mg BID. Therapy was continued over 1(1/2) years, with a tapering dose. After 2(1/2) years of continuous treatment, clinical and microbiological healing was achieved.