Concomitant pulmonary aspergillosis and nocardiosis in a patient with chronic granulomatous disease of childhood

Rare occurrence of pulmonary coinfection involving Aspergillus fumigatus and Nocardia cyriacigeorgica in immunocompetent patients based on NGS: A case report and literature review

RATIONALE

In our search on PubMed, we found that reports of co-infections involving Aspergillus fumigatus and Nocardia cyriacigeorgica in the literature are notably scarce. Most cases have been documented in patients with compromised immune systems or underlying pulmonary conditions. In contrast, our patient did not present with any of these risk factors. Furthermore, there have been no recent incidents such as near-drowning or other accidents in the patient history. To the best of our knowledge, this case represents a hitherto unreported clinical scenario. To enhance comprehension, we conducted a comprehensive literature review by compiling a total of 20 case reports (spanning from 1984 to 2023) on co-infections involving Aspergillus and Nocardia species, retrieved from PubMed.

PATIENT CONCERNS AND DIAGNOSIS

Chest CT revealed the presence of multiple nodules and clustered high-density shadows in both lungs. Bronchoscopy revealed mucosal congestion and edema in the apical segment of the right upper lobe of the lung, along with the presence of 2 spherical polypoid new organisms. The pathological analysis reported severe chronic inflammation with evidence of Aspergillus within the tissue. Next-Generation Sequencing of bronchoalveolar lavage fluid revealed the presence of reads corresponding to A fumigatus and N cyriacigeorgica. Positive cultures for A fumigatus and the Nocardia genus were yielded by prolonging the incubation of samples in the microbiology laboratory.

INTERVENTIONS

Treatment with voriconazole for A fumigatus and sulfamethoxazole-trimethoprim for N cyriacigeorgica infection was given.

OUTCOMES

The patient improved and was discharged. After 6 months of telephone follow-up, the patient reported no clinical symptoms, discontinued the medication on his own.

LESSONS

A fumigatus and N cyriacigeorgica can manifest as a co-infection in immunocompetent patients. Clinicians should prioritize the significant advantages and value of NGS in detecting rare and mixed pathogens associated with pulmonary infections.

Case of coexisting Nocardia cyriacigeorgica and Aspergillus fumigatus lung infection with metastatic disease of the central nervous system

Nocardiosis is a rare opportunistic gram-positive bacterial infection. The genus Nocardia consists of non-motile, aerobic, non-spore-forming, catalase-positive, filamentous-branching bacteria with fragmentation into coccoid or bacillary forms. Opportunistic infections due to Nocardia are reported in immunocompromised patients. Aspergillus fumigatus is a conidia forming fungus that can be found in soil, plant matter and dust, causing invasive pulmonary and disseminated infection in immunocompromised patients. Both Nocardia cyriacigeorgica and A. fumigatus are known to cause pulmonary infection with metastatic dissemination to the central nervous system. We present a case of Nocardia and Aspergillus co-infection in a patient who presented within a few days of initiation of immunosuppressants for suspected systemic lupus erythematosus.

Pulmonary co-infection with Nocardia and Aspergillus in a patient with adult-onset Still's disease receiving steroids and tacrolimus

Patients on immunosuppression are at risk of unusual infections. We present a man diagnosed to have adult-onset Still's disease who, on high-dose oral steroid and tacrolimus, developed a cavitating pneumonia due to co-infection with Aspergillus flavus and Nocardia. Timely diagnosis and institution of appropriate therapy resulted in a favourable clinical outcome. Such co-infection in a patient receiving tacrolimus is rare in the published literature. This case serves to emphasise the need to be vigilant for unusual infections in patients who are immunosuppressed, either due to drugs or underlying disease condition.

[Opportunistic co-infection in a patient with Crohn's disease during infliximab (anti-TNFalpha) therapy]

BACKGROUND

The biological therapies for chronic inflammatory diseases of autoimmune origin, particularly drugs inhibiting cytokines, such as the antagonists of the tumoral necrosis factor alpha (TNFalpha), are acceptably well tolerated in patients suffering rheumatologic, dermatologic and gastrointestinal pathologies. Nevertheless, pharmacologic vigilance studies have clarified several aspects of their security in daily clinical use. The adverse effects associated with inhibitors of TNFalpha can be related to the target (or class) and to the agent. The adverse effects related to the target include those potentially attributable to the inherent immunosuppressive state due to the blockade of the main cytokine, phenomenon that could increase the susceptibility to the infections and cancer.

AIMS

To expound the potential risk of serious infections, opportunistic or not, inherent to the use of biological therapies and, specifically, antagonistic drugs of TNFalpha, from the description of a case of invasive fungal infection.

METHODS

Revision of clinical records, obtained from the chronic inflammatory disease of autoimmune origin patient database, candidates or recipients of the new biological therapies, and study of the microbiological isolates.

RESULTS

A case of dual opportunistic infection (nocardiosis and aspergillosis) with a difficult diagnosis and complex management in an immunosupressed patient with Crohn's disease, triggered off after the administration of infliximab (monoclonal antibody anti-TNFalpha) is presented.

CONCLUSIONS

Invasive fungal infections, with isolated or associated clinical presentation to other opportunistic infections, are emerging in new groups-at-risk as they are the recipients of anti-cytokine biological therapies, regulators of inflammation and immunity. They can be potentially serious in their evolution and a high index of suspicion is needed sometimes for their prompt diagnosis. Possible preventive measures in patients with a high risk of suffering them will have to be investigated.

Invasive aspergillosis in chronic granulomatous disease

Chronic granulomatous disease (CGD) is an inherited disorder of the NADPH oxidase complex in which phagocytes are defective in generating superoxide anion and its metabolites. NADPH oxidase activation leads to activation of sequestered neutrophil proteases that mediate host defense. Invasive aspergillosis and other rarer mold diseases are the leading causes of mortality in CGD, reflecting the key role of the phagocyte NADPH oxidase in host defense against opportunistic fungi. Despite recombinant interferon-gamma prophylaxis, invasive filamentous fungal infections are a persistent problem in CGD. Key principles of management of fungal infections involve early recognition and aggressive treatment and appropriate surgical debridement of localized disease. Because CGD is a disorder of phagocyte stem cells in which the gene defects are well defined, it is a model disease to evaluate immune reconstitution through stem cell transplantation and gene therapy. Recent studies using CGD mice show that defects in tryptophan catabolism may underlie the impaired host defense and pathogenic inflammation in CGD and open the potential for novel therapeutic approaches; however, correlative studies in patients are required.

Bacterial Infections

In Osier’s time, bacterial pneumonia was a dreaded event, so important that he borrowed John Bunyan’s characterization of tuberculosis and anointed the pneumococcus, as the prime pathogen, “Captain of the men of death.”1 One hundred years later much has changed, but much remains the same. Pneumonia is now the sixth most common cause of death and the most common lethal infection in the United States. Hospital-acquired pneumonia is now the second most common nosocomial infection.2 It was documented as a complication in 0.6% of patients in a national surveillance study,3 and has been reported in as many as 20% of patients in critical care units.4 Furthermore, it is the leading cause of death among nosocomial infections.5 Leu and colleagues6 were able to associate one third of the mortality in patients with nosocomial pneumonia to the infection itself. The increase in hospital stay, which averaged 7 days, was statistically significant. It has been estimated that nosocomial pneumonia produces costs in excess of $500 million each year in the United States, largely related to the increased length of hospital stay.

Invasive aspergillosis in primary immunodeficiencies

Primary immunodeficiencies are rare and usually first manifest during childhood. Invasive aspergillosis is the leading cause of mortality in chronic granulomatous disease (CGD), reflecting the key role of the phagocyte NADPH oxidase in host defense against opportunistic fungi. Despite interferon-gamma prophylaxis, invasive filamentous fungal infections are a persistent problem in CGD. Key principles of management of fungal infections involve early recognition and aggressive treatment and appropriate surgical debridement of localized disease. Because CGD is a disorder of phagocyte stem cells in which the gene defects are well defined, it is a model disease to evaluate immune reconstitution through stem cell transplantation and gene therapy. Patients with the hyper-IgE syndrome with recurrent infections (Job syndrome) are prone to colonization of lung cavities (pneumatoceles) by Aspergillus species leading to local invasion and rarely disseminated infection. Other primary phagocytic disorders, T-cell disorders, and mitochondrial disorders are uncommonly associated with invasive aspergillosis. Taken together, these rare primary immunodeficiencies highlight the complex coordination of both innate and acquired pathways mediating host defense against Aspergillus infection.

Nocardia infection in chronic granulomatous disease

To determine the clinical characteristics and outcome of Nocardia infection in patients with chronic granulomatous disease (CGD), we reviewed data on 28 episodes of Nocardia infection in 23 patients with CGD. All episodes involved pulmonary infection. The frequency of disseminated nocardiosis was 25% for the case series overall, but it was 56% among episodes in patients receiving neither interferon-gamma (IFN-gamma) nor sulfonamide prophylaxis. Patients receiving prophylaxis with IFN-gamma and/or a sulfonamide were significantly less likely to have disseminated nocardiosis than were patients not receiving these medications, and no patient receiving both medications developed disseminated nocardiosis. One-third of the patients had concomitant fungal infections, and 2 patients had concomitant Legionella infections. The majority of patients were successfully treated with a sulfonamide-containing regimen, even though some patients had developed Nocardia infection while receiving sulfonamide prophylaxis. Nocardia infections in patients with CGD are not usually fatal if treated properly, and prophylaxis with IFN-gamma and a sulfonamide may protect against dissemination.

Disseminated nocardiosis in a patient with X-linked chronic granulomatous disease and human immunodeficiency virus infection

We report the first case of HIV infection in a patient with underlying X-linked chronic granulomatous disease (CGD) who presented with hepatopulmonary nocardiosis. Despite the coexistence of CGD and HIV, the response to therapy was normal, and no unusual sequelae were noted. The patient's high virus burden was successfully repressed with antiretroviral therapy, suggesting that the nicotinamide adenine dinucleotide phosphate oxidase system is not essential for active viral replication or response to antiretroviral agents.

Genetic, biochemical, and clinical features of chronic granulomatous disease

The reduced nicotinamide dinucleotide phosphate (NADPH) oxidase complex allows phagocytes to rapidly convert O2 to superoxide anion which then generates other antimicrobial reactive oxygen intermediates, such as H2O2, hydroxyl anion, and peroxynitrite anion. Chronic granulomatous disease (CGD) results from a defect in any of the 4 subunits of the NADPH oxidase and is characterized by recurrent life-threatening bacterial and fungal infections and abnormal tissue granuloma formation. Activation of the NADPH oxidase requires translocation of the cytosolic subunits p47phox (phagocyte oxidase), p67phox, and the low molecular weight GT-Pase Rac, to the membrane-bound flavocytochrome, a heterodimer composed of the heavy chain gp91phox and the light chain p22phox. This complex transfers electrons from NADPH on the cytoplasmic side to O2 on the vacuolar or extracellular side, thereby generating superoxide anion. Activation of the NADPH oxidase requires complex rearrangements between the protein subunits, which are in part mediated by noncovalent binding between src-homology 3 domains (SH3 domains) and proline-rich motifs. Outpatient management of CGD patients relies on the use of prophylactic antibiotics and interferon-gamma. When infection is suspected, aggressive effort to obtain culture material is required. Treatment of infections involves prolonged use of systemic antibiotics, surgical debridement when feasible, and, in severe infections, use of granulocyte transfusions. Mouse knockout models of CGD have been created in which to examine aspects of pathophysiology and therapy. Gene therapy and bone marrow transplantation trials in CGD patients are ongoing and show great promise.

Nocardia farcinica pneumonia in chronic granulomatous disease

Infection with Nocardia poses a diagnostic challenge in patients with chronic granulomatous disease (CGD) because the signs and symptoms are often nonspecific, delay in diagnosis is common, and invasive procedures are frequently required to obtain appropriate tissue specimens. We present the first reported case of N farcinica pneumonia in an adolescent with X-linked CGD. Differentiation of N farcinica from other members of N asteroides complex is important because of its propensity for causing disseminated infection and antimicrobial resistance. Physicians caring for patients with CGD should maintain a high index of suspicion for nocardiosis, especially in those receiving chronic steroid therapy. Early diagnosis remains critical for decreased morbidity and occasional mortality.

The medically important aerobic actinomycetes: epidemiology and microbiology

The aerobic actinomycetes are soil-inhabiting microorganisms that occur worldwide. In 1888, Nocard first recognized the pathogenic potential of this group of microorganisms. Since then, several aerobic actinomycetes have been a major source of interest for the commercial drug industry and have proved to be extremely useful microorganisms for producing novel antimicrobial agents. They have also been well known as potential veterinary pathogens affecting many different animal species. The medically important aerobic actinomycetes may cause significant morbidity and mortality, in particular in highly susceptible severely immunocompromised patients, including transplant recipients and patients infected with human immunodeficiency virus. However, the diagnosis of these infections may be difficult, and effective antimicrobial therapy may be complicated by antimicrobial resistance. The taxonomy of these microorganisms has been problematic. In recent revisions of their classification, new pathogenic species have been recognized. The development of additional and more reliable diagnostic tests and of a standardized method for antimicrobial susceptibility testing and the application of molecular techniques for the diagnosis and subtyping of these microorganisms are needed to better diagnose and treat infected patients and to identify effective control measures for these unusual pathogens. We review the epidemiology and microbiology of the major medically important aerobic actinomycetes.

Nocardia species: host-parasite relationships

The nocardiae are bacteria belonging to the aerobic actinomycetes. They are an important part of the normal soil microflora worldwide. The type species, Nocardia asteroides, and N. brasiliensis, N. farcinica, N. otitidiscaviarum, N. nova, and N. transvalensis cause a variety of diseases in both normal and immunocompromised humans and animals. The mechanisms of pathogenesis are complex, not fully understood, and include the capacity to evade or neutralize the myriad microbicidal activities of the host. The relative virulence of N. asteroides correlates with the ability to inhibit phagosome-lysosome fusion in phagocytes; to neutralize phagosomal acidification; to detoxify the microbicidal products of oxidative metabolism; to modify phagocyte function; to grow within phagocytic cells; and to attach to, penetrate, and grow within host cells. Both activated macrophages and immunologically specific T lymphocytes constitute the major mechanisms for host resistance to nocardial infection, whereas B lymphocytes and humoral immunity do not appear to be as important in protecting the host. Thus, the nocardiae are facultative intracellular pathogens that can persist within the host, probably in a cryptic form (L-form), for life. Silent invasion of brain cells by some Nocardia strains can induce neurodegeneration in experimental animals; however, the role of nocardiae in neurodegenerative diseases in humans needs to be investigated.

Pneumonia caused by Nocardia nova and Aspergillus fumigatus after cardiac transplantation

Nocardia nova, a newly established species of the Nocardia asteroides complex, has recently been characterized as a human pathogen. This report of a case of pneumonia caused by Nocardia nova and Aspergillus fumigatus in a patient after cardiac transplantation is the first reported infection caused by Nocardia nova following its detailed description. Accurate identification and susceptibility testing of the Nocardia nova isolate allowed successful oral therapy with clarithromycin when therapy with sulfisoxazole was not tolerated.

Microgranulomatous aspergillosis after shoveling wood chips: report of a fatal outcome in a patient with chronic granulomatous disease

Chronic granulomatous disease is characterized by recurrent infections that result from an inability of phagocytes to kill organisms effectively. We describe a patient with this disease who developed aspergillus pneumonia after shoveling moldy cedar wood chips. Despite aggressive therapy, the patient's condition deteriorated and he died. At autopsy, the lungs revealed diffuse granulomas, all of the same age, with aspergillus organisms confined to the granulomas. We propose the term "microgranulomatous aspergillosis" for this response, which does not conform to the commonly described aspergillus syndromes. We conclude that susceptible immunosuppressed patients should be advised to avoid occupational situations where high spore concentrations are generated.

Primary cutaneous aspergillosis associated with Hickman intravenous catheters

We describe nine patients with underlying hematologic cancer in whom primary cutaneous aspergillosis developed at the sites of Hickman intravenous catheters. Our patients, 17 to 74 years of age, were all immunocompromised either from their primary disease or from chemotherapy, and the Hickman catheters had been placed to provide venous access for chemotherapy or hyperalimentation or both. Clinical signs of infection included erythema, induration, and cutaneous or subcutaneous necrosis at the point of entry into the subclavian vein, in the subcutaneous tunnel, or at the exit site from the skin. Diagnosis was confirmed by positive wound culture for Aspergillus flavus in all but one patient. Treatment consisted of intravenous amphotericin B, oral flucytosine, and local wound care. Three patients recovered completely without operative débridement; three others recovered after operative débridement and delayed grafting. Two patients died of disseminated aspergillosis, and one died of unrelated causes while recovering from primary cutaneous aspergillosis. Successful treatment required resolution of aplasia or leukopenia, catheter removal, systemic treatment with amphotericin B, and local wound care. We conclude that primary cutaneous aspergillosis, a rare infection, may occur at the sites of Hickman catheters in immunocompromised patients, and that it is a serious complication requiring prompt diagnosis and treatment.

Aspergillus myositis in a patient with a myelodysplastic syndrome

We present the case of an elderly man who, while being treated with corticosteroids for a myelodysplastic syndrome, developed myositis of the calf due to Aspergillus fumigatus. Despite therapy with amphotericin B the myositis failed to resolve and he died. At autopsy, a localized necrotizing myositis of the right calf was found with no evidence of disseminated Aspergillus infection. Myositis in the setting of disseminated candidiasis or cryptococcosis has been previously reported. This case is unique in that it is the first reported case of localized fungal myositis and of myositis caused by Aspergillus.