[Lymphomas in immunocompromised patients]. / Lymphomes de l'immunodéprimé.

Immunosuppression is a well known risk factor for the development of lymphoid pathologies. The classification of these neoplasias is becoming more precise and complex, some features being common to all immunocompromised patients, primarily the important influence of Epstein-Barr virus. Whatever the origin of the immunodepression, these lymphoid proliferations are very heterogeneous, constituting a wide range between polymorphic aspects and clearly lymphomatous morphologies indistinguishable from those observed in immunocompetent subjects. It is important to detect precisely these different categories of proliferation within each group of immunosuppression, to better individualize the prognosis and the management of patients.

[Monoclonal gammopathy of undetermined significance (MGUS): interpretative shades of analysis and sometimes serious clinical consequences]. / Point sur les GMSI : interprétation des examens complémentaires et complications cliniques.

The etiological assessment of a monoclonal gammopathy is currently standardized, the decisional algorithms allowing a sufficiently precise classification to consider the care, wait or therapeutic. The purpose of this review is to recall the difficulties concerning the interpretation of certain biological investigations and to point out the potential complications of monoclonal gammopathies labeled as "benign". The cooperation between clinicians and biologists is in all cases essential, allowing to propose on a case-by-case basis the best adapted explorations.

[IgM Myeloma: case report and literature review]. / Myélome à IgM : à propos d'un cas et revue de littérature.

The presence of serum monoclonal IgM is often associated with the diagnosis of Waldenström macroglobulinemia (WM) or other chronic lymphoproliferative disorders. IgM myeloma is a rare entity (0.5%). We report the case of an IgM myeloma complicated by systemic amyloidosis AL, with an impure nephrotic syndrome and a factor FX deficiency.

[Renal involvement during type 1 cryoglobulinemia]. / Atteinte rénale au cours des cryoglobulinémies de type 1.

Cryoglobulins are circulating immunoglobulins that precipitate with cold temperature and dissolve with rewarming. Type 1 cryoglobulinemia is composed of a single monoclonal immunoglobulin and is associated with renal involvement in up to 40% of cases. Type 1 cryoglobulinemia is related to an underlying B-cell haematological malignancy in 60% of patients. In the remaining cases, in the absence of criteria for malignancy, the diagnosis of monoclonal gammopathy of renal significance should be established. The clinical and biological setting and histological features of type 1 cryoglobulinemia are globally similar to those of mixed cryoglobulinemia. In case of haematological malignancy, the treatment is guided by the nature of the underlying disease, and aims at inducing haematological remission, which is necessary for the renal response. The management of monoclonal gammopathy of renal significance has been clarified by an international consensus group and is based on the nature of the underlying clone. In case of monoclonal cryoglobulinemia associated with a plasma-cell clone (IgG or IgA), the treatment is based on the combination of bortezomib, cyclophosphamide and dexamethasone. In case of IgM monoclonal cryoglobulinemia, the treatment is similar to that of Waldenström macroglobulinemia, and is based on rituximab. The clinical course of renal monoclonal cryoglobulinemia is intimately associated with the haematological response, and is usually favourable.

Bilateral renal cortical necrosis with end-stage renal failure following envenoming by Proatheris superciliaris: a case report.

Acute bilateral renal cortical necrosis (BRCN) has been reported following envenoming by exotic venomous snakes. Proatheris superciliaris is a rare viper with restricted distribution in east Africa. Very little information is available on envenoming by this species. We herein describe the case of a 60-year-old professional wildlife photographer who was bitten on his thumb while photographing an adult specimen of P. superciliaris that he held at home in France. On admission, physical examination revealed severe hypertension and bruising with edema at the bite site. Within the following 24 h, he developed vomiting, diarrhea, acute lumbar pain and anuria. Laboratory tests showed acute kidney injury (serum creatinine 4.6 mg/dL), with thrombocytopenia, anemia and severe coagulopathy. Contrast-enhanced computed tomography scan revealed hypodense areas in the cortex of both kidneys consistent with diffuse BRCN. As no appropriate antivenom existed, only symptomatic care was given to the patient. Coagulation tests returned to normal within 48 h. The patient was placed on chronic hemodialysis, until he underwent successful kidney transplantation 18 months later. In developed countries, severe complications provoked by snake bites tend to be more frequent with the number of trendy exotic pets. Acute kidney injury, including BRCN, is a classic complication of viper bites. The present case of end-stage renal failure related to diffuse BRCN illustrates the potentially devastating effects of envenoming by P. superciliaris. Clinicians in developed countries should be informed about renal disorders and other potentially fatal complications of venomous snake bites and seek urgent expert advice for optimizing clinical management. Education and coaching of envenomed patients and exotic snake owners is mandatory to prevent dramatic accidents.