Pulmonary infection caused by Rhodococcus equi in a kidney and pancreas transplant recipient: a case report

Pneumonia in solid organ transplantation: Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These guidelines from the AST Infectious Diseases Community of Practice review the diagnosis and management of pneumonia in the post-transplant period. Clinical presentations and differential diagnosis for pneumonia in the solid organ transplant recipient are reviewed. A two-tier approach is proposed based on the net state of immunosuppression and the severity of presentation. With a lower risk of opportunistic, hospital-acquired, or exposure-specific pathogens and a non-severe presentation, empirical therapy may be initiated under close clinical observation. In all other patients, or those not responding to the initial therapy, a more aggressive diagnostic approach including sampling of tissue for microbiological and pathological testing is warranted. Given the broad range of potential pathogens, a microbiological diagnosis is often key for optimal care. Given the limited literature comparatively evaluating diagnostic approaches to pneumonia in the solid organ transplant recipient, much of the proposed diagnostic algorithm reflects clinical experience rather than evidence-based data. It should serve as a template which may be modified according to local needs. The same holds true for the suggested empiric therapies, which need to be adapted to the local resistance patterns. Further study is needed to comparatively evaluate diagnostic and empiric treatment strategies in SOT recipients.

Antibiotic failure in a renal transplant patient with Rhodococcus equi infection: an indication for surgical lobectomy

Rhodococcus equi is an animal pathogen that causes infrequent but challenging infections in immunocompromised individuals, few of which have been described in solid organ transplant recipients. Common clinical presentations include indolent cough, fever, and dyspnea, with necrotizing pneumonia and cavitation. We report a case of a dense right upper lung pneumonia with resultant R. equi bacteremia in a renal transplant recipient. Our patient initially responded to antibiotic treatment with resolution of bacteremia and clinical recovery, followed by interval progression in her right upper lobe consolidation on follow-up computed tomography scans. She underwent lobectomy for definitive therapy with resolution of symptoms. Lobectomy can be utilized in isolated infection after antibiotic failure with excellent clinical outcomes.

Persistent Rhodococcus equi infection in a renal transplant patient: case report and review of the literature

Rhodococcus equi is a pathogen that mainly causes infection in immunocompromised hosts. We report a case of relapsing R. equi pulmonary infection in a 57-year-old male renal transplant recipient who was treated with 12 months of antibiotics, adjunctive surgery, and a reduction in his immunosuppression. He suffered from relapsing disease, treatment-related complications, and ultimately died of Pneumocystis pneumonia. Case reports in the literature portray a good cure rate for transplant-related R. equi infections, with shorter durations of antibiotics. The case illustrates the difficulties in the management of R. equi infections. Forty cases from the literature were reviewed and compared in terms of epidemiology, location of infection, transplant type, immunosuppression used, treatment used, outcomes, and possible exposures.

Rhodococcal lung abscess in a renal transplant recipient

Background:

Rhodococcus species are relatively rare human pathogens, but are being increasingly recognized as causes of infection especially in immunosuppressed patients.

Case Report:

We present a case of Rhodococcus lung abscess in a patient 10 months post-cadaveric renal transplant, successfully treated with a combination of antibiotics. She required a prolonged course of oral antibiotics for 6 months. She did not require surgical intervention. Chest X-rays and CT thorax showed complete resolution of the initial lesion. We also review the medical literature related to Rhodococcus infection in patients with renal transplantation. Rhodococcus infection should be considered as in the differential diagnosis of immunosuppressed patients who present with lung abscess/mass.

Conclusions:

A literature review indicates this is a potentially fatal condition with disseminated sepsis/abscesses.

Rhodococcus lung abscess complicating kidney transplantation: successful management by combination antibiotic therapy

In this report, a renal transplant recipient with Rhodococcus lung abscess is described. A high clinical suspicion and appropriate combination antibiotic therapy obviated the need for surgical intervention and was associated with a good clinical outcome. The optimal regimen of combination antibiotic therapy is discussed.

Zoonoses in Solid-Organ and Hematopoietic Stem Cell Transplant Recipients

Numerous reports exist of the transmission of zoonoses to humans during and after solid-organ and hematopoietic stem cell transplantation. Donor-derived infections of numerous etiologies, including West Nile virus infection, Chagas disease, toxoplasmosis, rabies, lymphocytic choriomeningitis virus infection, and infection due to Brucella species have been reported. Most zoonoses occur as a primary infection after transplantation, and immunocompromised patients are more likely to experience significant morbidity and mortality from these infections. Risks of zoonotic infection in the posttransplantation period could be reduced by patient education. Increased recognition of the risks of zoonoses, as well as the advent of molecular biology-based testing, will potentially augment diagnostic aptitude. Documented zoonotic infection as it affects transplantation will be the primary focus of this review.

Infections in solid organ transplant recipients

A disturbing trend in evolution for sometime has culminated in the fact that resistant Gram-positive bacteria including enterococci and staphylococci have emerged as the leading pathogens at many transplant centers. Recently published reports have highlighted the formidable challenge such antimicrobial-resistant microorganisms now pose in transplant recipients. Studies published within the past year have documented the clinical relevance of human herpesvirus-6 after transplantation, as well as the transmission of human herpesvirus-8 by transplanted allograft and the subsequent development of Kaposi's sarcoma in these patients. A novel hepatitis virus has been discovered; studies to elucidate its significance in the transplant setting are underway.

Rhodococcus equi pneumonia in a renal transplant patient: a case report and review of literature

Immunocompromised patients are susceptible to many pathogens, including those that are predominantly problems in veterinary medicine. We report a case of a 42-yr-old white male who presented 19 months post-cadaveric renal transplant (for IgA nephropathy) with a 5 d history of nausea, vomiting, abdominal cramping and diarrhea. Admission chest X-ray revealed a suspicious mass lesion in the left lower lobe. Computed tomography (CT) guided biopsy of the lesion showed a large zone of CD68 +ve histiocytes in a non-caseating granuloma. Gram stain revealed multiple gram-positive rods within the histiocytes, which were eventually identified as R. equi. After 4 months of therapy with fluoroquinolones (Avelox) and Azithromycin a repeat CT showed complete resolution of the lesion. We reviewed the literature with special focus on the clinical features, challenges in diagnosis, and treatment of this rare infection (especially in the transplant patients who are also on immunosuppressive therapy).

Role of surgery in Rhodococcus equi pulmonary infections

Rhodococcus equi (R. equi) is a soil-dwelling bacterium that is increasingly associated with pulmonary infections in immunocompromised patients. While antibiotic therapy remains the cornerstone of treatment, surgery combined with antibiotics has an important role in select cases. We report two cases of pulmonary R. equi in immunocompromised patients who were treated with antibiotics, followed by surgical resection of the infected tissues, and then long-term antibiotics. Both patients had excellent outcomes. We advocate surgical resection of grossly infected pulmonary tissue as an adjunct to antimicrobial therapy for treatment of this uncommon, but potentially lethal pathogen.

Rhodococcus equi: an emerging pathogen

More than 100 cases of Rhodococcus equi infection have been reported since the first description of human disease caused by this organism. The vast majority of patients infected with R. equi are immunocompromised, and two-thirds have human immunodeficiency virus infection. The clinical manifestations of R. equi infection are diverse, although 80% of patients have some pulmonary involvement. The organism is easily cultured from specimens of infected tissue or body fluid, but it may be misdiagnosed as a contaminant. Treatment is often prolonged, and relapses at distant sites are common. This article summarizes the history, diagnosis, clinical features, and treatment of infection with this emerging pathogen.

Rhodococcus equi pulmonary infection in a pancreas-alone transplant recipient: consequence of intense immunosuppression

We report the case of a pancreas-alone transplant recipient who developed Rhodococcus equi pneumonia after receiving multiple courses of antilymphocyte therapy for the treatment of recurrent acute pancreas allograft rejection. We also review and discuss the diagnosis, clinical course, and treatment of 18 cases of R. equi infection reported in solid organ transplant recipients. The lung is the most common primary site of infection, but R. equi infection is difficult to diagnose because of the pleomorphic, gram-positive, and partially acid-fast nature of the organism. Treatment usually involves a combination of antibiotics including rifampin, macrolides, vancomycin, and ciprofloxacin. The optimal duration of therapy is unknown, but relapse is common if the duration of treatment is less than 14 days. The duration of therapy should be guided by clinical recovery, culture results, and radiographic findings. Monitoring levels of immunosuppressive agents-such as tacrolimus and cyclosporine-is needed in order to avoid clinically significant drug interactions with rifampin or the macrolides when these agents are used in order to treat R. equi infection in the transplant population.

Medical management of pneumonia caused by Rhodococcus equi in a renal transplant recipient

Rhodococcus equi is an animal pathogen that occasionally causes opportunistic infections in immunocompromised patients. The most common clinical picture is one of necrotizing pneumonia with a tendency toward cavitation and the formation of abscesses. We report a case of pneumonia caused by R equi in a renal transplant patient. An excellent response was shown to antibiotic treatment. Symptoms regressed, and the progressive disappearance of the lesion was confirmed on follow-up computed tomography scans. Surgical intervention or other invasive procedures were not required. To our knowledge, 14 cases of infection by R equi in solid-organ transplant patients have been described to date. Nine were recipients of a renal allograft. Surgery was required in many of these patients, and all the renal transplant recipients required the use of invasive therapeutic techniques, such as pleural drainage. This is the first case of a renal transplant recipient in whom radiologic presentation was as a solid nodule without ensuing cavitation that resolved exclusively with antibiotic treatment.

Late-onset renal failure after liver transplantation: role of posttransplant alcohol use

BACKGROUND

Late-onset renal failure is being increasingly recognized as a complication in patients undergoing liver transplantation for hepatitis C virus (HCV). However, its precise incidence, predisposing risk factors, and impact on outcome after liver transplantation, have not been defined.

METHODS

The development of late-onset renal failure (defined as serum creatinine persistently >2.0 mg/dl, occurring more than 6 months posttransplant) was assessed in 120 consecutive liver transplant recipients who survived at least 6 months after transplantation. Fifty-seven percent (68/120) of the patients had undergone transplantation for liver disease due to HCV. The median follow-up was 5 years.

RESULTS

Late-onset renal failure developed in 28% (33/120)of the patients. Posttransplant alcohol use (P=0.0001), posttransplant diabetes (P=0.0042), and recurrent HCV hepatitis (P=0.019) were significantly associated with late onset renal failure. In multivariate analysis, alcohol use (O.R. 10.7, 95%; CI 2.4-35.9, P=0.001) and diabetes (O.R. 2.1, 95%; CI 1.1-9.9, P=.03) were independently significant predictors of late onset renal failure. When only patients transplanted for HCV were analyzed, posttransplant alcohol use (P=0.004) was the only significant independent predictor of late-onset renal failure. HCV genotype 1b, as compared with other HCV genotypes, was associated with a higher rate of late-onset renal failure in patients with HCV; 70% of the patients with genotype 1b versus 32% of those with 1a and 33% of those with 2b, developed late onset renal failure (P=0.03). At a median follow up of 5 years, mortality in patients with HCV with late-onset renal failure was 52% as compared with 2% in those without renal failure (P=.0001).

CONCLUSION

Late-onset renal failure in patients with HCV portended a grave outcome. Alcohol use was an independent predictor of late-onset renal failure in patients with HCV and represents a potentially modifiable risk factor for late-onset renal failure in these patients.