Retrospective analysis of nocardiosis in a general hospital from 1998 to 2017

Nocardiosis: a single-center experience and literature review

INTRODUCTION

Nocardiosis is a rare bacterial infection caused by Nocardia spp. However, an increasing incidence has been described whereby data about epidemiology and prognosis are essential.

METHODS

A retrospective descriptive study was conducted among patients with positive Nocardia spp. culture, from January 2019 to January 2023, at a Terciary Hospital in Portugal.

RESULTS

Nocardiosis was considered in 18 cases with a median age of 63.8-years-old. At least one immunosuppressive cause was identified in 70% of patients. Five patients had Disseminated Nocardiosis (DN). The lung was the most common site of clinical disease (77.8%) and Nocardia was most commonly identified in respiratory tract samples. The most frequently isolated species were Nocardia nova/africana (n = 7) followed by Nocardia cyriacigeorgica (n = 3) and Nocardia pseudobrasiliensis (n = 3). The majority of the patients (94.4%) received antibiotic therapy, of whom as many as 55.6% were treated with monotherapy. The most frequently prescribed antibiotic was trimethoprim-sulfamethoxazole. Selected antimicrobial agents were generally effective, with linezolid and cotrimoxazole (100% Susceptibility [S]) and amikacin (94% S) having the most activity against Nocardia species. The median (IQR) duration of treatment was 24.2 (1‒51.4) weeks for DN; The overall one-year case fatality was 33.3% (n = 6) and was higher in the DN (66.7%). No recurrence was observed.

CONCLUSION

Nocardiosis is an emerging infectious disease with a poor prognosis, particularly in DN. This review offers essential epidemiological insights and underscores the importance of gaining a better understanding of the microbiology of nocardiosis. Such knowledge can lead to the optimization of antimicrobial therapy and, when necessary, guide appropriate surgical interventions to prevent unfavorable outcomes.

Unusual presentation of Nocardia abscessus infection in an immunocompetent patient

Introduction. Nocardia infections are being increasingly reported in both immunocompetent and immunocompromised patients. We describe a case of Nocardia abscessus infection with an atypical presentation in an immunocompetent patient.

Case Presentation. A previously healthy 47-year-old gentleman presented with hiccups and paroxysmal spasms. Imaging revealed a pulmonary nodule, for which he underwent surgical resection. Pathologic evaluation demonstrated evidence of local inflammation, with growth of Nocardia abscessus on tissue cultures.

Conclusion. Nocardia abscessus may have atypical presentations in immunocompetent patients. Further research is needed to understand the factors leading to Nocardia infections in immunocompetent patients.

Clinical features and prognosis of nocardiosis in patients with connective tissue diseases

OBJECTIVES

To investigate the clinical features and prognosis of nocardiosis complicated by connective tissue diseases (CTDs).

METHODS

We examined patients with CTDs who were diagnosed with nocardiosis from October 2004 to 2019. We retrospectively investigated patient characteristics and therapeutic outcomes. We then performed a comparison between survivors and non-survivors.

RESULTS

Fourteen patients were examined. Underlying CTDs were systemic lupus erythematosus (28.6%), vasculitis syndrome (28.6%), rheumatoid arthritis (21.4%), adult Still disease (14.3%) and dermatomyositis (7.1%). Infected organs were lung (85.7%), brain (42.9%), skin/cutaneous lesions (28.6%) and muscle (7.1%). Disseminated infections were seen in nine patients (64.3%). At the onset of nocardiosis, all patients were given prednisolone (23.2 ± 11.9 mg/day). Only two patients (14.3%) were given TMP-SMX for prophylaxis of pneumocystis pneumonia. Relapse occurred in one patient (7.1%) and four patients (28.6%) died from nocardiosis for a cumulative survival rate at 52 weeks of 76.9%. In a comparison of survivors (71.4%) and non-survivors (28.6%), cutaneous lesions were significantly more frequent in the latter (10 vs 75%, p = .04) with an odds ratio of 27.0 (95% CI: 1.7-453.4).

CONCLUSION

Cutaneous lesions as a result of dissemination might be a risk factor for nocardiosis mortality in patients with CTDs.

18F-FDG Imaging of a Case of Disseminated Nocardiosis

Nocardiosis is an uncommon infection caused by ubiquitous environmental aerobic gram-positive filamentous bacteria, present in soil and water. Skin and lungs are usually the main targets of localized infections. Rarely, disseminated forms can occur in immunocompromised individuals. A 63-year-old man with a history of late-onset asthma and nasal and sinus polyposis treated with oral low-dose corticosteroid regimen presented with fever, headache, myalgia, skin erythematous plaques, and pustules. Brain MRI revealed multiple abscesses and pachymeningitis. F-FDG PET/CT was performed to assess the extent of the infection. Cutaneous samples and sputum culture isolated Nocardia brasiliensis, confirming diagnosis of disseminated nocardiosis.

Nocardia bacteremia: A single-center retrospective review and a systematic review of the literature

OBJECTIVES

Nocardia bacteremia is a rare but severe disease associated with high mortality. This systematic review is the largest and most comprehensive review performed over the past 20 years.

METHODS

A single-center retrospective review of Nocardia bacteremia was performed using hospital microbiology records from January 1, 2010 to December 31, 2017. A systematic literature review was also performed to identify cases of Nocardia bacteremia described in the NCBI PubMed database in English between January 1, 1999 and December 31, 2018.

RESULTS

Four new cases of Nocardia bacteremia are described. The systematic review identified 134 cases with sufficient information available for analysis. Of the total 138 cases, the median age was 58 years (interquartile range (IQR) 44-69 years) and 70% were male. Eighty-one percent were immunocompromised (corticosteroid use (49%), hematological malignancy (20%), solid organ transplant (20%), solid organ malignancy (19%), and hematopoietic stem cell transplantation (15%)) and 29% had endovascular devices. Pulmonary infection was the most common concurrent site of clinical disease (67%). The median incubation time to the detection of Nocardia bacteremia was 4 days (IQR 3-6 days). Blood cultures were the only positive microbiological specimen in 38% of cases. The median total duration of treatment was 75 days (IQR 25-182 days). Thirty-day all-cause mortality was 28% and overall all-cause mortality was 40%.

CONCLUSIONS

Nocardia bacteremia is most frequently identified in immunocompromised patients and those with intravascular devices. Although rare, it represents a serious infection with high associated overall mortality.