Nocardia Infection in Nephrotic Syndrome Patients: Three Case Studies and A Systematic Literature Review.

OBJECTIVE: The multicenter literature review and case studies of 3 patients were undertaken to provide an updated understanding of nocardiosis, an opportunistic bacterial infection affecting immunosuppressed nephrotic syndrome (NS) patients receiving long-term glucocorticoid and immunosuppressant treatment. The results provided clinical and microbiological data to assist physicians in managing nocardiosis patients. METHODS: Three cases between 2017 and 2018 from a single center were reported. Additionally, a systematic review of multicenter cases described in the NCBI PubMed, Web of Science, and Embase in English between January 1, 2001 and May 10, 2021 was conducted. RESULTS: This study described three cases of Nocardia infection in NS patients. The systematic literature review identified 24 cases with sufficient individual patient data. A total of 27 cases extracted from the literature review showed that most patients were > 50 years of age and 70.4% were male. Furthermore, the glucocorticoid or corticosteroid mean dose was 30.9 ± 13.7 mg per day. The average time between hormone therapy and Nocardia infection was 8.5 ± 9.7 months. Pulmonary (85.2%) and skin (44.4%) infections were the most common manifestations in NS patients, with disseminated infections in 77.8% of patients. Nodule/masses and consolidations were the major radiological manifestations. Most patients showed elevated inflammatory biomarkers levels, including white blood cell counts, neutrophils percentage, and C-reactive protein. Twenty-five patients received trimethoprim-sulfamethoxazole monotherapy (18.5%) or trimethoprim-sulfamethoxazole-based multidrug therapy (74.1%), and the remaining two patients (7.4%) received biapenem monotherapy. All patients, except the two who were lost to follow-up, survived without relapse after antibiotic therapy. CONCLUSIONS: Nephrotic syndrome patients are at high risk of Nocardia infection even if receiving low-dose glucocorticoid during the maintenance therapy. The most common manifestations of nocardiosis in NS patients include abnormal lungs revealing nodules and consolidations, skin and subcutaneous abscesses. The NS patients have a high rate of disseminated and cutaneous infections but a low mortality rate. Accurate and prompt microbiological diagnosis is critical for early treatment, besides the combination of appropriate antibiotic therapy and surgical drainage when needed for an improved prognosis.

Nocardia Infections: Ten Years Experience from a Tertiary Health Care Center in North India (2007-2016).

BACKGROUND: Nocardia species are important cause of infections in humans but are underreported due to missed diagnosis as well as misdiagnosis. Majority of the literature on these infections consists of case reports or series with few articles describing high number of cases. OBJECTIVE: To study the epidemiology of Nocardia infections in a tertiary care center. MATERIALS AND METHODS: This retrospective observational study was done in a tertiary care centre of North India over a period of 10 years (2007-2016). The detection of Nocardia spp. from clinical specimens was done by conventional methods viz. direct microscopy (Gram's stain, modified Ziehl -Neelsen stain [1%], KOH examination) and culture. RESULTS: A total of 25 cases of nocardiosis were diagnosed during the study period. The mean age of the patients was 50.9 years (range 30-72 years) with a male:female ratio of 3:2. The site of disease in these patients included pulmonary (n=18), cutaneous (n=4), perinephric abscess (n=1), ocular (n=1) and bone (n=1). Risk factors associated were underlying lung disease (n=11), smoking (n=7), diabetes (n=5) and steroid therapy (n=4) in pulmonary nocardiosis, iatrogenic (n=1) and leprosy (n=1) in cutaneous nocardiosis, diabetes in perinephric abscess and cataract surgery in ocular nocardiosis. Culture was positive in 12/25 (48%) patients for Nocardia spp. Direct microscopy was positive in 22 patients. We wish to highlight that meticulous observation of KOH wet mount examination helped in clinching the diagnosis of Nocardiosis in 3 cases which were earlier missed by other methods. CONCLUSION: Good communication with the clinician alongside a meticulous effort in the laboratory is essential for appropriate diagnosis and management of these cases.

Left thigh phlegmon caused by Nocardia farcinica identified by 16S rRNA sequencing in a patient with leprosy: a case report.

BACKGROUND: In recent years, Nocardia farcinica has been reported to be an increasingly frequent cause of localized and disseminated infections in the immunocompromised patient. However, recent literature is limited. We report a case of left thigh phlegmon caused by N. farcinica that occurred in a patient with leprosy undergoing treatment with prednisone for leprosy reaction. CASE PRESENTATION: We describe the case of left thigh phlegmon caused by Nocardia farcinica in a 54-year-old Italian man affected by multi-bacillary leprosy. The patient had worked in South America for 11 years. Seven months after his return to Italy, he was diagnosed with leprosy and started multi-drug antibiotic therapy plus thalidomide and steroids. Then, during therapy with rifampicin monthly, minocycline 100 mg daily, moxifloxacin 400 mg daily, and prednisone (the latter to treat type 2 leprosy reaction), the patient complained of high fever associated with erythema, swelling, and pain in the left thigh. Therefore, he was admitted to our hospital with the clinical suspicion of cellulitis. Ultrasound examination and Magnetic Resonance Imaging showed left thigh phlegmon. He was treated with drainage and antibiotic therapy (meropenem and vancomycin replaced by daptomycin). The responsible organism, Nocardia farcinica, was identified by 16S rRNA sequencing in the purulent fluid taken out by aspiration. The patient continued treatment with intravenous trimethoprim/sulfamethoxazole and imipenem followed by oral trimethoprim/sulfamethoxazole and moxifloxacin. A whole-body computed tomography did not reveal dissemination to other organs like the lung or brain.The patient was discharged after complete remission. Oral therapy with trimethoprim/sulfamethoxazole, moxifloxacin, rifampicin monthly, clofazimine and thalidomide was prescribed to be taken at home. One month after discharge from the hospital the patient is in good clinical condition with complete resolution of the phlegmon. CONCLUSION: N. farcinica is a rare infectious agent that mainly affects immunocompromised patients. Presentation of phlegmon only without disseminated infection is unusual, even in these kinds of patients. In any case, a higher index of suspicion is needed, as diagnosis can easily be missed due to the absence of characteristic symptoms and the several difficulties usually encountered in identifying the pathogen.

Nocardia nova mycetoma over forehead in a lepromatous leprosy patient.

We present a case of a 31-year-old male, a known patient with lepromatous leprosy with a type 2 lepra reaction, who presented with a slowly growing asymptomatic swelling with multiple discharging sinuses over the forehead that developed over 6 months. Smears of the serosanguinous discharge on Gram staining showed Gram-positive branching filamentous bacilli, which on culture on blood agar showed chalky-white colonies. Histology of the lesion showed suppurative granulomas with polymorphs surrounding characteristic grains. The isolate was identified as Nocardia nova by gene sequencing and the patient was started on combined antibiotic therapy that resulted in complete resolution of the infection in six months. To the best of our knowledge, this is the first report of mycetoma related to Nocardia nova in association with leprosy.

Nocardial mycetoma: diverse clinical presentations.

Nocardia spp are gram-positive, aerobic, acid-fast bacteria which exist as saprophytes in nature. Invasive disseminated infections are particularly common in immunocompromised or debilitated hosts. Superficial infections with Nocardia spp occur as a result of local trauma and contamination of the wound. Clinically, it presents as acute infection (abscesses or cellulitis), mycetoma, or sporotrichoid infection. Differential diagnosis includes eumycetoma, chromomycosis, blastomycosis, coccidioidomycosis, sporotrichosis, tuberculosis, botryomycosis, syphilis, yaws, and neoplasia. Its diagnosis is confirmed by demonstrating the causative organism in exudates (as granules), tissue specimens, or cultures. Early diagnosis will obviate need for drastic surgical measures as early institution of chemotherapy is effective in most patients. However, its diagnosis is often delayed due to diverse clinical presentations and for want of clinical suspicion, particularly in non-endemic areas. This paper presents 4 clinical forms of this not so uncommon disease, emphasizing the importance of high index of clinical suspicion, especially in non-endemic regions; and the significance of repeated examination of exudates for Nocardia granules for an early diagnosis.

[Minocycline]. / Minocycline.

Minocycline belongs to the second generation class of cyclines. It was synthesized in 1967 and marketed in 1972. Minocycline has an antiinfectious activity with a spectrum similar to that of other cyclines, notably against Chlamydias, Treonema and Proprionibacterium acenes. The antiinflammatory activity is associated with this antiinfectious action is greater than that of first generation cyclines with specifically a modulator effect on epidermal cytokines. The pharmokinetics of minocycline is characterized by an excellent absorption, a long half-life and an important lipophilic property inducing good tissue distribution. Clinical trials of minocycline have mainly been performed in sexually transmissible diseases and in acne, a field where randomized studies are the most frequent. These trials show that the effect of minocycline is not stronger than first generation cyclines or doxycycline, but that the action is quicker than that of tetracycline at the dose of 500 mg a day. Minocycline is also efficient in nocardiasis, mycobacteriosis, leprosy, Lyme disease, pyoderma gangrenosum, autoimmune bullous dermatitis, Carteaud disease, and prurigo. However, the effect of minocycline in these different conditions has always been evaluated in open trials with a small number of patients. The usual side effects of cyclines, i.e. digestive problems, fungal infections, are less frequent than with first generation cyclines. No photosensitivity has been demonstrated although pigmentations have been described. Dizziness is a specific side effect of minocycline. Furthermore, rare but severe side effects have been reported, including hypersensitivity syndrome, autoimmune hepatitis, and lupus. Regular indications for minocycline in dermatology are acne and three sexually transmissible diseases (mycoplasm, chlamydia, treponema). Proposed dosage is 100 mg per day in sexually transmissible disease with a reduction to 50 mg per day after 15 days in acne.