Background Kidney diseases associated with immunoglobulin M (IgM) monoclonal gammopathy are poorly described, with few data for patient outcomes and renal response. Study Design Case series. Setting ...& Participants 35 patients from 8 French departments of nephrology were retrospectively studied. Inclusion criteria were: (1) detectable serum monoclonal IgM, (2) estimated glomerular filtration rate (eGFR) < 60 mL/min/1.73 m2 and/or proteinuria with protein excretion > 0.5 g/d and/or microscopic hematuria, and (3) kidney biopsy showing monoclonal immunoglobulin deposits and/or lymphomatous B-cell renal infiltration. All patients received chemotherapy, including rituximab-based regimens in 8 cases. Predictors Patients were classified into 3 groups according to renal pathology: glomerular AL amyloidosis (group 1; n = 11), nonamyloid glomerulopathies (group 2; n = 15, including 9 patients with membranoproliferative glomerulonephritis), and tubulointerstitial nephropathies (group 3; n = 9, including cast nephropathy in 5, light-chain Fanconi syndrome in 3, and isolated tumor infiltration in 1). Outcomes Posttreatment hematologic response (≥50% reduction in serum monoclonal IgM and/or free light chain level) and renal response (≥50% reduction in 24-hour proteinuria or eGFR ≥ 30 mL/min/1.73 m2 in patients with glomerular and tubulointerstitial disorders, respectively). Results Nephrotic syndrome was observed in 11 and 6 patients in groups 1 and 2, respectively. Patients in group 3 presented with acute kidney injury (n = 7) and/or proximal tubular dysfunction (n = 3). Waldenström macroglobulinemia was present in 26 patients (8, 12, and 6 in groups 1, 2, and 3, respectively). Significant lymphomatous interstitial infiltration was observed in 18 patients (4, 9, and 5 patients, respectively). Only 9 of 29 evaluable patients had systemic signs of symptomatic hematologic disease (2, 5, and 2, respectively). In groups 1, 2, and 3, respectively, hematologic response was achieved after first-line treatment in 3 of 9, 9 of 10, and 5 of 6 evaluable patients, while renal response occurred in 5 of 10, 9 of 15, and 5 of 8 evaluable patients. Limitations Retrospective study; insufficient population to establish the impact of chemotherapy. Conclusions IgM monoclonal gammopathy is associated with a wide spectrum of renal manifestations, with an under-recognized frequency of tubulointerstitial disorders.
Background Neutrophilic dermatoses refer to a group of cutaneous inflammatory disorders characterized by neutrophilic infiltration of the skin. Neutrophilic dermatoses have been reported in ...association with various conditions including autoimmune diseases, inflammatory bowel diseases, and neoplasia. In the later condition, myeloproliferative disorders and monoclonal gammopathy (monoclonal immunoglobulin MIg) are the most frequent. Only few data are available in case of neutrophilic dermatoses associated with MIg regarding the pathophysiology and the clinical outcome. Objective We sought to gain further insight into clinical and biological aspects of neutrophilic dermatoses associated with MIg. Methods We report a retrospective series of 26 patients with neutrophilic dermatoses associated with MIg focusing on clinical and biological aspects, with a study of a large panel of cytokines, chemokines, and adhesion molecules. Results This study reveals an association between MIg IgA isotype and neutrophilic dermatoses, and a specific inflammatory pattern including elevated interleukin 6, vascular endothelial growth factor, monocyte chemotactic protein-1, epidermal growth factor, and intercellular adhesion molecule-1. Limitations This is a retrospective study from a single institution with a limited number of participants. Conclusion Our data highlight a strong association between IgA isotype and neutrophilic dermatoses, and the existence of a specific inflammatory profile involving several molecules.
To the best of our knowledge, only 3 cases of cutaneous polyarteritis nodosa (PAN) treated successfully with methotrexate (MTX) have been reported in the medical literature. We report 2 further cases ...of steroid-dependent cutaneous PAN treated successfully with low-dose weekly MTX therapy. The clinical and biological tolerance of MTX was excellent. The cutaneous lesions started to regress within 3 weeks. One of the patients reported full recovery which lasted 2 years after stopping the therapy. So, MTX seems to be an interesting therapy in the treatment of PAN because of its relatively low toxicity, its simple use, its quick action and prolonged results after MTX has been stopped.
