Hemorrhagic Herpes Simplex Virus Type 1 Nephritis: An Unusual Cause of Acute Allograft Dysfunction.

Interstitial nephritis due to viruses is well-described after solid organ transplantation. Viruses implicated include cytomegalovirus; BK polyomavirus; Epstein-Barr virus; and, less commonly, adenovirus. We describe a rare case of hemorrhagic allograft nephritis due to herpes simplex virus type 1 at 10 days after living donor kidney transplantation. The patient had a favorable outcome with intravenous acyclovir and reduction of immunosuppression.

A novel mouse model of podocyte depletion.

AIM: The goal of this study was to examine the capacity for glomerular repair after a podocyte-depleting injury. METHODS: We created transgenic (TG) mice expressing the yeast enzyme cytosine deaminase specifically in glomerular podocytes. In these TG animals, the prodrug 5-flucytosine (5-FC) is converted to 5-fluorouracil and promotes cell death. RESULTS: Treatment with increasing dosages of 5-FC caused graded increases in proteinuria 1-2 weeks after treatment, which returned to control levels by the 10-week time point. Light microscopic examination revealed minimal pathology at the 2-week time point, but electron microscopy revealed found foot process effacement as well as focal areas of glomerular basement membrane duplication, and immunohistochemical studies detected podocyte apoptosis and a decrease in the number of Wilms' tumor protein 1 (WT1)-positive cells. By the 10-week time point, however, the number of WT1-positive cells was similar to controls and a few mice had developed focal areas of glomerulosclerosis. Consistent with the effects of 5-FC on podocyte number, expression of the podocyte mRNAs for nephrin, podocin, synaptopodin and podocalyxin were altered in a similar temporal fashion. CONCLUSION: The glomerulus has a significant capacity for repair after a podocyte-depleting injury.

Fatal Apophysomyces elegans infection transmitted by deceased donor renal allografts.

Two patients developed renal mucormycosis following transplantation of kidneys from the same donor, a near-drowning victim in a motor vehicle crash. Genotypically, indistinguishable strains of Apophysomyces elegans were recovered from both recipients. We investigated the source of the infection including review of medical records, environmental sampling at possible locations of contamination and query for additional cases at other centers. Histopathology of the explanted kidneys revealed extensive vascular invasion by aseptate, fungal hyphae with relative sparing of the renal capsules suggesting a vascular route of contamination. Disseminated infection in the donor could not be definitively established. A. elegans was not recovered from the same lots of reagents used for organ recovery or environmental samples and no other organ transplant-related cases were identified. This investigation suggests either isolated contamination of the organs during recovery or undiagnosed disseminated donor infection following a near-drowning event. Although no changes to current organ recovery or transplant procedures are recommended, public health officials and transplant physicians should consider the possibility of mucormycosis transmitted via organs in the future, particularly for near-drowning events. Attention to aseptic technique during organ recovery and processing is re-emphasized.

Symptomatic pulmonary allograft Kaposi's sarcoma in two lung transplant recipients.

Kaposi's sarcoma (KS) is associated with solid-organ transplantation, but is extremely rare after lung transplantation. In this report, we describe two unique cases of lung transplant recipients who developed KS in the lung allograft and were treated with sirolimus and liposomal doxorubicin. One patient survived 12 months after the diagnosis of KS; the other survived 3 months after diagnosis and was found to have concomitant EBV-negative, HHV-8-positive B-cell lymphoma. We demonstrate a partial response of pulmonary KS to reduced immunosuppression and the initiation of sirolimus in one patient, as well as an association between increasing HHV-8 viremia and progression of pulmonary KS. Our report highlights the importance of secondary malignancies in patients with transplant-related KS and supports the association between HHV-8 infection and EBV-negative PTLD.

Successful bilateral lung transplantation for lymphangiomatosis.

Lymphangiomatosis is a rare disease of lymphatic proliferation for which no adequate treatment is known. We report the first successful case of bilateral lung transplantation for the treatment of end-stage pulmonary lymphangiomatosis. A successful outcome was achieved with continued survival beyond 4 years posttransplant and stable lung function. The primary obstacles to significant gains in pulmonary function were thoracic, skeletal and abdominal lymphangiomatosis, which led to pulmonary restriction. Our report demonstrates that pulmonary lymphangiomatosis should be included among those diseases for which lung transplantation is considered potentially beneficial treatment but also emphasizes the importance of screening patients carefully for chest wall and abdominal lymphangiomas that may impede recovery.

Chronic aspiration of gastric fluid induces the development of obliterative bronchiolitis in rat lung transplants.

Long-term survival of a pulmonary allograft is currently hampered by obliterative bronchiolitis (OB), a form of chronic rejection that is unique to lung transplantation. While tracheobronchial aspiration from gastroesophageal reflux disease (GERD) has clinically been associated with OB, no experimental model exists to investigate this problem. Using a WKY-to-F344 rat orthotopic left lung transplant model, the effects of chronic aspiration on pulmonary allograft were evaluated. Recipients received cyclosporine with or without 8 weekly aspirations of gastric fluid into the allograft. Six (66.7%) of 9 allografts with aspiration demonstrated bronchioles with surrounding monocytic infiltrates, fibrosis and loss of normal lumen anatomy, consistent with the development of OB. In contrast, none of the allografts without aspiration (n = 10) demonstrated these findings (p = 0.002). Of the grafts examined grossly, 83% of the allografts with chronic aspiration but only 20% without aspiration appeared consolidated (p = 0.013). Aspiration was associated with increased levels of IL-1 alpha, IL-1 beta, IL-6, IL-10, TNF-alpha and TGF-beta in BAL and of IL-1 alpha, IL-4 and GM-CSF in serum. This study provides experimental evidence linking chronic aspiration to the development of OB and suggests that strategies aimed at preventing aspiration-related injuries might improve outcomes in clinical lung transplantation.

Lambda light chain deposition disease in a renal allograft.

Light chain deposition disease (LCDD) of the kidney is characterized by deposition of monoclonal light chains predominantly in glomeruli and in tubular basement membranes. The disease is frequently associated with a lymphoproliferative disorder, and the majority of cases are caused by deposition of kappa light chains. Although the occurrence of de novo multiple myeloma after renal transplantation is uncommon, there are several reports of LCDD involving renal allografts, either de novo or in patients with a diagnosis of LCDD prior to transplantation. To the best of our knowledge, all previously described cases in allografts have been in patients with kappa chain deposition. The relative importance of intrinsic properties of the kidney in predisposing to either kappa or lambda light chain deposition is not known. We present a case of LCDD caused by deposition of lambda light chains in a patient who received a cadaveric renal transplant.

Clinical significance of eosinophils in suspicious or borderline renal allograft biopsies.

AIMS: Renal allograft biopsies play a critical role in renal transplantation. Acute rejection characterized by tubulitis and intimitis is of primary concern. There is an association between eosinophilic infiltrates and irreversible acute rejection; however, the significance of eosinophils in biopsies that fall short of the diagnostic threshold for acute rejection has not been well studied. This report describes clinical course, treatment and long-term outcome of 5 transplant recipients with biopsy histology that showed borderline changes associated with eosinophilic infiltrates. METHODS: Clinical records were selected for review on the basis of biopsy histology satisfying the following criteria: presence of interstitial infiltrates with eosinophils, absence of definitive criteria for acute rejection and absence of findings suggestive of infection or cyclosporine toxicity. RESULTS: All identified biopsies occurred within the first month of transplantation, and histology showed varying degrees of patchy mononuclear cell infiltrates composed of lymphocytes, with eosinophilic infiltrates, but no evidence of acute rejection based on Banff criteria. These patients were taking trimethoprim-sulfamethoxazole and ranitidine at the time of biopsy. Serum creatinine returned to baseline levels in each case after stopping both drugs, and remained stable during the duration of follow-up without any documented episode of acute rejection. No patient received specific therapy for acute rejection. CONCLUSION: This report suggests that independent of decisions on treatment with high-dose steroids or anti-lymphocyte antibody preparations, the management algorithm should include stopping drugs associated with acute interstitial nephritis when non-diagnostic biopsies show eosinophilic infiltrates.