Duodenal villous atrophy: a cause of chronic diarrhea after solid-organ transplantation.

Persistent diarrhea is commonly observed after solid organ transplantation (SOT). A few cases of mycophenolate mofetil (MMF)-induced duodenal villous atrophy (DVA) have been previously reported in kidney-transplant patients with chronic diarrhea. Herein, we report on the incidence and characteristics of DVA in SOT patients with chronic diarrhea. One hundred thirty-two SOT patients with chronic diarrhea underwent an oesophago-gastroduodenoscopy (OGD) and a duodenal biopsy after classical causes of diarrhea have been ruled out. DVA was diagnosed in 21 patients (15.9%). It was attributed to mycophenolic acid (MPA) therapy in 18 patients (85.7%) (MMF [n = 14] and enteric-coated mycophenolate sodium [n = 4]). MPA withdrawal or dose reduction resulted in diarrhea cessation. The incidence of DVA was significantly higher in patients with chronic diarrhea receiving MPA compared to those who did not (24.6% vs. 5.1%, p = 0.003). DVA was attributed to a Giardia lamblia parasitic infection in two patients (9.5%) and the remaining case was attributed to azathioprine. In these three patients, diarrhea ceased after metronidazole therapy or azathioprine dose reduction. In conclusion, DVA is a frequent cause of chronic diarrhea in SOT recipients. MPA therapy is the most frequent cause of DVA. An OGD should be proposed to all transplant recipients who present with persistent diarrhea.

Viral infections after kidney transplantation.

Chronic immunosuppression, required to maintain allograft function postorgan transplant, predisposes transplant patients to a variety of viral infections. These can occur at every stage of post-transplantation. Some infections, however, such as cytomegalovirus (CMV), Epstein Barr virus (EBV), or BK virus (BKV), tend to occur within months after transplantation. CMV infections can be easily prevented by prophylaxis therapy whereas EVB or BKV infections can be prevented by lowering (when possible) immunosuppression. Some viral infections can result in posttransplant lymphoproliferative disorders (EBV), Kaposi sarcoma (human herpes simplex virus type 8), or skin and/or cervical cancers (papillomavirus). Other viral infections, such as those due to influenza or para influenzae viruses, respiratory syncytial virus, or West nile fever virus, are mostly acquired through environmental spread. Thanks to modern laboratory technique, and a formidable antiviral armamentarium, viral infections in organ transplant patients i) can be easily detected at early stages, and ii) can be efficiently treated.

Rationale for using belatacept in combination with sirolimus.

Kidney transplantation can be used to replace failing native kidneys; however, it requires long-term immunosuppression, and immunological tolerance for this is not yet achievable. The cornerstone of immunosuppression is based on calcineurin inhibitors, which are nephrotoxic. Therefore, new drugs are being developed that provide efficacious immunosuppression and almost no renal toxicity. The first family of drugs that have these properties are mammalian target of rapamycin inhibitors: these include sirolimus and everolimus. These two drugs, besides their immunosuppressive properties, also have beneficial effects regarding cytomegalovirus (CMV) infection, which is a very common posttransplantation complication. In phase III trials, belatacept, a costimulatory blocker, has also been shown to provide a good immunosuppressive effect and also gives a significantly better cardiovascular profile than cyclosporine-based immunosuppression. However, belatacept can potentially increase infections such as CMV. Thus, herein, we describe the rationale for combining belatacept with sirolimus for kidney transplant patients.

Relapse of membranous glomerulopathy after kidney transplantation: sustained remittance induced by rituximab.

Membranous glomerulopathy (MG) is a rare cause of chronic kidney disease. However, after kidney transplantation (KT), despite immunosuppression, it often relapses on the allograft. Herein, we report on a male kidney-transplant patient, aged 27 years, who developed overt nephrotic syndrome 11 months after KT. This was related to relapsing MG, as evidenced by the allograft biopsy, which, in addition, showed CD3 (+) and CD20 (+) interstitial lymphocyte infiltration. The patient was treated with rituximab: 375 mg/m2/week for 4 consecutive weeks, followed by one additional injection every 3 months for one year. Remission was observed before the third rituximab injection. After a follow-up of 42 months, the patient was still in remission, i.e., microalbuminuria of 107 mg/day.

Aspergillus fumigatus-related spondylodiscitis in a heart transplant patient successfully treated with voriconazole.

Organ transplant patients, such as heart transplant (HT) recipients, are prone to infections, among which are yeast infections. Of these, aspergillosis is usually associated with pneumopathy or facial sinusitis, and Aspergillus fumigatus is rarely responsible for osteomyelitis or spondylodiscitis. Herein we have reported a case of an 18-year-old male HT patient presenting with subacute lumbar spondylodiscitis at 6 months posttransplantation and 3 months after antirejection therapy with antithymocyte globulins. A percutaneous needle biopsy of the intervertebral disc yielded Aspergillus fumigatus. The patient had no evidence of lung aspergillosis, but did have maxillary sinusitis. He was successfully treated with voriconazole.