Disseminated Nocardia asteroides complex infection in an immunocompromised child

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.

[Disseminated nocardiosis in a child with acute lymphoblastic leukemia]

Nocardiosis is a rare infectious disease in children. We report here a disseminated nocardiosis in a child with acute lymphoblastic leukemia. The patient presented prolonged febrile neutropenia and nodular pneumopathy. Based on the amplification of a 16S rDNA, a PCR assay detected Nocardia sp. in the patient's bronchoalveolar lavage (BAL) fluid. Culture of BAL samples yielded Nocardia nova colonies after 2 weeks of incubation. Hepatic, splenic, renal and cerebral localisations were detected on extension checkup. trimethoprime-sulfamethoxazole and amikacine were started given the results of PCR assay, with a good response. Improvement of the patient's general condition led to complete chemotherapy under ciprofloxacine and ceftriaxone treatment, without nocardiosis reactivation. Nocardiosis is a rare complication in children with acute lymphoblastic leukemia. trimethoprime-sulfamethoxazole prophylaxis is widely used to prevent Pneumocystis jiroveci infection in children with haematologic malignancies. As Nocardia species are usually sensible, trimethoprime-sulfamethoxazole could play a role in Nocardia prophylaxis in such population. In our patient, compliance with trimethoprime-sulfamethoxazole had been low. Nocardia species are relatively fastidious growth bacteria and are difficult to isolate with classical bacteriological techniques. Molecular methods are now available, with a good sensitivity and fast results allowing to start an appropriate antibiotherapy before culture results, as early treatment is a major prognosis factor in nocardiosis. Nocardia infection should be suspected in case of nodular pneumopathy in immunocompromised children. An extension checkup should be performed to detect secondary localisations.

Disseminated nocardiosis in an immunocompetent child

We report a 2-month-old child with a disseminated Nocardia farcinica infection that presented with suppurative lymphatic abscess. The child did not have any predisposing factors and responded to treatment with co-trimoxazole and amikacin. This is first case report of disseminated nocardiosis caused by Nocardia farcinica in an immunocompetent child.