Disseminated nocardiosis in a bone marrow transplant recipient with chronic GVHD

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.

An Unusual Presentation of Nocardiosis in an Allogeneic Transplant Recipient

Nocardiosis is a rare cause of opportunistic infection post hematopoietic stem cell transplant (HSCT) occurring in about 0.3% of patients. The risk factors include delayed immune reconstitution, prolonged neutropenia, and graft-versus-host disease. The most common site of infection is the lung, followed by the brain and the skin. Concomitant pulmonary and central nervous system (CNS) nocardiosis is an extremely rare entity as presented in our case. We present the case of a 72-year-old male at 137 days post transplant presenting with complaints of headache and slurred speech. A magnetic resonance imaging (MRI) brain scan revealed two ring-enhancing lesions: 1.6 cm in the right frontal lobe and 1 cm in the left parietal lobe. The patient had an outpatient computed tomography (CT) chest scan a month prior showing a 1.4 cm solid right upper lobe nodule prompting bronchoalveolar lavage (BAL) that was nondiagnostic. On repeat inpatient CT chest scan, the nodule had increased in size to 3.3 x 2.5 x 2.1 cm, prompting a percutaneous fine-needle aspiration biopsy. He was started on empiric trimethoprim-sulfamethoxazole (TMP-SMX) and liposomal amphotericin B. The tissue mycology and acid-fast cultures were reported positive for nocardia species. The patient was discharged on intravenous TMP-SMX. A follow-up CT chest scan and MRI brain scan four months later showed resolution of the right upper lobe nodule and significant decrease in size of the brain lesions. The patient will continue TMP-SMX for a total of nine to 12 months. Given the increase in transplant recipients and the ongoing risk of developing nocardiosis several months post transplant, there is a need for standardized diagnostic and treatment guidelines. Meanwhile, our case highlights the importance of aggressiveness in pursuing a prompt diagnosis including invasive procedures, if required, in order to begin specific treatment.

Central nervous system infections in cancer patients and hematopoietic stem cell transplant recipients

Central nervous system (CNS) infections in cancer patients present a diagnostic and therapeutic challenge for clinicians. While CNS infections are not frequent complications of cancer, its therapies, or hematopoietic stem cell transplantation, the importance of CNS infections lies in their propensity to result in profound morbidity and substantial mortality in this vulnerable patient population. With an expanding population of patients with malignant disease undergoing more potent and aggressive therapies and with the advent of newer immunomodulatory agents, the incidence of CNS infectious complications is likely to rise. This chapter will summarize the clinical and diagnostic evaluation of potential infections of the CNS in these patients and will discuss particular pathogens of interest with regard to this at-risk patient population.

Nocardiosis in transplant recipients

Nocardiosis is a rare opportunistic infection caused by Nocardia spp., an aerobic actinomycete, that mainly affects patients with cell-mediated immunity defects, such as transplant recipients. Despite recent progress regarding Nocardia identification and changes in taxonomic assignment, many challenges remain for the diagnosis or management of nocardiosis. This opportunistic infection affects 0.04 to 3.5 % of patients with solid organ or hematopoietic stem cell transplantation, depending on the organ transplanted, cytomegalovirus (CMV) infection, corticosteroids dose and calcineurin inhibitors level. Nocardiosis diagnosis relies on appropriate clinical, radiological and microbiological workup that includes the sampling of an accessible involved site and molecular microbiology tools. In parallel, extensive clinical and radiological evaluations are mandatory, including brain imaging, even in the absence of neurological signs. In transplanted patients, differential diagnosis is challenging, with co-infections reported in 20 to 64 % of cases. As the antibiotic susceptibility pattern varies among species, the antimicrobial regimen before species identification should rely on the association of antibiotics active on all species of Nocardia. Bactericidal antibiotics are required in cases of severe or disseminated disease. Furthermore, in transplant recipients, combination therapy is difficult to manage because of cumulative toxicity and interactions with immunosuppressive agents. Because of a high recurrence rate, antibiotic therapy should be prescribed for 6 to 12 months.

Fatal Nocardia farcinica Bacteremia Diagnosed by Matrix-Assisted Laser Desorption-Ionization Time of Flight Mass Spectrometry in a Patient with Myelodysplastic Syndrome Treated with Corticosteroids

Nocardia farcinica is a Gram-positive weakly acid-fast filamentous saprophytic bacterium, an uncommon cause of human infections, acquired usually through the respiratory tract, often life-threatening, and associated with different clinical presentations. Predisposing conditions for N. farcinica infections include hematologic malignancies, treatment with corticosteroids, and any other condition of immunosuppression. Clinical and microbiological diagnoses of N. farcinica infections are troublesome, and the isolation and identification of the etiologic agent are difficult and time-consuming processes. We describe a case of fatal disseminated infection in a patient with myelodysplastic syndrome, treated with corticosteroids, in which N. farcinica has been isolated from blood culture and identified by Matrix-Assisted Laser Desorption-Ionization Time of Flight Mass Spectrometry. The patient died after 18 days of hospitalization in spite of triple antimicrobial therapy. Nocardia farcinica infection should be suspected in patients with history of malignancy, under corticosteroid therapy, suffering from subacute pulmonary infection,and who do not respond to conventional antimicrobial therapy. Matrix-Assisted Laser Desorption-Ionization Time of Flight Mass Spectrometry can be a valuable tool for rapid diagnosis of nocardiosis.

Pulmonary nocardiosis developed in a hematopoietic stem cell transplant recipient with bronchiolitis obliterans

The chronic graft-versus-host disease often requires unceasing immunosuppressive therapy (IST), which increases a risk of infectious complications in hematopoietic stem cell transplantation (HSCT) recipients. We report an adult T-cell leukemia/lymphoma case who developed pulmonary nocardiosis, a rare pulmonary complication, after allogeneic HSCT despite administration of the prophylactic trimethoprim-sulfamethoxazole (TMP/STX). The inhaled corticosteroid in addition to systemic IST had been started for bronchiolitis obliterance 4 months prior to nocardiosis development. The patient was successfully treated with an increased dose of TMP/STX combined with meropenem. Transplantation physicians should keep this rare pulmonary complication in mind during sustained IST.

Disseminated Nocardia farcinica infection in a uraemia patient with idiopathic thrombocytopenia purpura receiving steroid therapy

Nocardia farcinica has been reported as an increasingly frequent cause of localized and disseminated infections in immunocompromised patients in recent years, but N. farcinica bacteraemia remains a rare finding. Here, the case is described of a 68-year-old man with end-stage renal disease and idiopathic thrombocytopenia purpura treated with steroid therapy who developed disseminated infection (bacteraemia, multilobar pneumonia and brain abscesses) due to N. farcinica. The isolate was confirmed by partial sequencing analysis of the 16S rRNA gene. The patient recovered after prolonged trimethoprim-sulfamethoxazole therapy with no recurrence in over 1 year.

Fatal Nocardia farcinica bacteremia in a patient with lung cancer

Nocardia farcinica is an emerging pathogen in immunocompromised patients, accounting for approximately 20% of Nocardia clinical isolates in various countries. A case of fatal N. farcinica bacteremia in a 52-year-old man with lung cancer is described. He was admitted with severe respiratory distress, and despite the early onset of empirical antibiotic treatment, he failed to respond and died of septic shock 24 hours later. N. farcinica was isolated from blood cultures obtained at hospital admission and was identified by conventional methods. Strain identification was confirmed by nucleotide sequencing of the 16S rRNA gene. N. farcinica bacteremia is a life-threatening infection. Because of the actinomycete's highly-resistant antibiotic profile, early identification and antibiotic susceptibility testing are necessary to improve the chances of survival.

Pulmonary nocardiosis in a patient with CML relapse undergoing imatinib therapy after bone marrow transplantation

We describe a case of pulmonary nocardiosis in a female patient with graft-versus-host disease (GVHD) underwent therapy with imatinib mesylate for a relapse of chronic myeloid leukemia (CML) after allogeneic bone marrow transplantation (BMT). The patient developed chronic GVHD 8 months after the use of imatinib and was on corticosteroid therapy. Three months after the development of chronic GVHD, she acquired pulmonary nocardiosis and a computed tomography (CT) scan of the chest showed multiple nodular lesions with cavitations over both lungs. She was successfully treated with single-agent trimethoprim-sulfamethoxazole (TMP/SMX) and the infection did not recur. Our case indicated that pulmonary nocardiosis could occur in patients with GVHD undergoing imatinib and corticosteroid therapy and might be treated by single-agent TMP/SMX.

Nocardiosis: a review

Infections caused by Nocardia species are infrequent but challenging to clinicians. They cause a wide variety of diseases in both normal and immunocompromised patients. In recent years, the number of case reports has been increasing, and this can be attributed to the improvements in diagnostic capabilities and the higher clinical index of suspicion accompanying the increased prevalence of immunosuppressed patients. The treatment of nocardiosis also requires expertise. This report reviews the epidemiology, physiopathology, clinical manifestations, diagnosis and treatment of this aerobic bacterial disease.

Multi-system Infection with Nocardia farcinica-therapy with linezolid and minocycline

We describe a case of disseminated infection with a multiple-resistant strain of Nocardia farcinica, probably resulting from direct inoculation during a road traffic accident. Initial presentation was with pulmonary symptoms, with subsequent development of cutaneous, renal, soft tissue and cerebral involvement. Precise microbiological diagnosis was delayed. Once sensitivity test results were available, the patient was stabilised on linezolid and minocycline. Premature withdrawal of therapy at one month resulted in recrudescence of infection, requiring re-institution of treatment. Linezolid was discontinued after a total of 4 months, because of evidence of myelosuppression and visual impairment, which subsequently improved. Monotherapy with minocycline was continued for a total of 12 months. The patient now remains well.

Systemic nocardiosis following allogeneic bone marrow transplantation

Five cases of systemic Nocardia infection were diagnosed among 301 allogeneic bone marrow transplant recipients. A sixth case included in this report received her transplant at another institution. The cumulative annual incidence rate of this infection was 1.75%. All patients had been treated previously for acute graft-versus-host disease (GVHD). At the time of diagnosis of systemic Nocardia infection, a median of 198 (range 148-1121) days after transplantation, all patients had extensive chronic GVHD and were taking 2 to 3 immunosuppressive medications. Prior to diagnosis of Nocardia infection patients had experienced multiple opportunistic infections, including infections with Mycobacterium avium-intracellulare, Pneumocystis carinii, and cytomegalovirus antigenemia. Treatment with trimethoprim-sulfamethoxazole (TMP-SMX), ceftriaxone, or carbapenem antibiotics resulted in a median survival of 219 days from the time of diagnosis and an actuarial 1-year survival of 40%. All patients who received more than 2 weeks of therapy were cured of their infections. Notably, 5/6 patients in this cohort were unable to take TMP-SMX because of myelosuppression. In comparison with randomly selected control patients, the use of pentamidine for prevention of P. carinii infection was associated with a marginal increase in the risk of Nocardia infection. We postulate that the use of TMP-SMX may be of benefit in the prophylaxis of infections other than P. carinii in patients with chronic GVHD.

Infectious complications in patients undergoing unrelated donor bone marrow transplantation: experience from a single institution

OBJECTIVE

To analyze the incidence and characteristics of documented infections in patients with hematologic malignancies undergoing unrelated donor bone marrow transplantation (UD-BMT).

METHODS

We studied the occurrence of infections in 22 patients with hematologic malignancies or severe aplastic anemia who underwent UD-BMT from April 1990 to December 2000. The median age was 26 years (range 13-46). Acyclovir-ganciclovir, co-trimoxazole, fluconazole-nystatin and ciprofloxacin were administered for anti-infectious prophylaxis.

RESULTS

We registered 61 infectious episodes. During the early post-transplant period, there were eight clinically documented infections (CDIs), four cases of fever of unknown origin (FUO), seven cases of bacteremia, two cases of cytomegalovirus (CMV) antigenemia, and one case of CMV disease. In the intermediate period (days 30-100 after BMT), there were nine cases of CMV antigenemia, three bacterial infections, two fungal infections, one case of disseminated toxoplasmosis, and one case of FUO. In the late period (day 100 and later), we documented 13 viral infections, eight bacterial infections, one CDI, and one case of invasive aspergillosis. Infections contributed to death in 10 of 17 patients. Citrobacter bacteremia and sepsis of unknown origin were the main causes of infectious mortality in the early period. Infection was the main cause of death in six of seven patients in the late period.

CONCLUSION

A high incidence of life-threatening infections and infection-related mortality was observed. A high rate of CMV infection in the early period, and death caused by multiresistant Gram-negative microorganisms in the late period, were the main findings in this series.

Nocardiosis in cancer patients

Nocardiosis (NOC) is an important cause of infection in immunocompromised patients. However, large series in patients with cancer have not been described. We review the records of patients with cancer and NOC who were evaluated at The University of Texas M. D. Anderson Cancer Center, Houston, Texas, between 1988 and 2001, and we describe the incidence, microbiologic and clinical characteristics, treatment, and outcome of NOC in this population. Forty-two patients with a total of 43 episodes of NOC were identified (incidence of 60 cases of NOC per 100,000 admissions). Twenty-seven patients (64%) had hematologic malignancies. In 13 patients, NOC complicated bone marrow transplantation. Neutropenia was observed in 4 (10%) of 40 episodes with information available, and lymphopenia in 20 (50%) of 40 episodes. Patients had received steroids for 25 episodes (58%) and had received chemotherapy for 10 episodes (23%) within 30 days before the onset of NOC. Nine episodes of breakthrough NOC were identified in 7 (23%) of the 40 patients with information available. Pulmonary NOC was seen in 30 (70%) of 43 cases; soft-tissue NOC in 7 (16%); central venous catheter-related nocardemia in 3 (7%); and disseminated NOC, central nervous system NOC, and a perinephric abscess each in 1 (2%). Twenty-three percent of patients with pulmonary NOC had an acute presentation. complex was the most common causative species (77%). Therapy for NOC was mainly concurrent trimethoprim/ sulfamethoxazole and either a tetracycline or a beta-lactam. The median duration of treatment was 113 days (range, 10-600 d). Nine (60%) of 15 patients with outcome data died from NOC. NOC, although infrequent, is an important cause of morbidity and mortality in patients with cancer. It has pleomorphic manifestations, and it can be seen as a breakthrough infection. The present study confirms that timely diagnosis, the site of NOC, the type of, the presence of comorbidities, and cytomegalovirus coinfection influence the outcome of patients with cancer and NOC.

Opportunistic infections after renal transplantation

Opportunistic infection is a serious clinical complication in patients receiving immunosuppressive therapy after kidney transplantation. This article deals with some of the possible infectious agents that were recently encountered at our transplantation centre in Düsseldorf, Germany. Opportunistic organsims such as human herpesviruses 6-8, polyomavirus, parvovirus B19, varicella zoster virus, Nocardia and Listeria monocytogenes are rare but severe complications that are presented in this overview. As a result of the use of new immunosuppresive drugs like tacrolimus and mycophenolate mofetil these infections are now seen more frequently, so they should always be included in differential diagnostic considerations. New diagnostic procedures and new treatment strategies should allow early detection and successful treatment of opportunistic infections in the majority of kidney transplant recipients.

Pulmonary Nocardiosis

Pulmonary nocardiosis is an uncommon but serious infection that is increasingly found in immunosuppressed persons, especially transplant recipients and persons with AIDS. The Nocardia species are denizens of soil and decaying plants that gain entry to humans through inhalation or inoculation. Pulmonary nocardiosis typically presents as an acute to subacute necrotizing pneumonia, with a variable clinical picture. Metastatic infections of the brain and subcutaneous tissues are common complications. Most clinical laboratories can isolate these microorganisms, but final speciation may be a challenge and antimicrobial susceptibility testing is especially difficult because of the slow rate of growth of Nocardia species. Full identification of species and susceptibility testing is important because of the epidemiologic implications and the difficulties of successfully treating these infections in immunosuppressed patients. Sulfonamides, including trimethoprim-sulfamethoxazole, remain the most reliable antimicrobials. Many alternative agents are active against Nocardia in vitro, but clinical data are limited.