Monoclonal Immunoglobulin Crystalline Membranous Nephropathy.

Monoclonal immunoglobulin (MIg) crystalline nephropathies are rare lesions resulting from precipitation of MIgs in the kidney as intracellular or extracellular crystals. We describe a patient with multiple myeloma (IgGλ) and diabetes who presented with nephrotic range proteinuria. Kidney biopsy revealed membranous nephropathy superimposed on diabetic glomerulosclerosis. Glomeruli were negative for PLA2R, THSD7A, and NELL-1. Ultrastructurally, the subepithelial deposits were composed of crystals (ranging from rhomboid to rod to needle shaped), which failed to stain for immunoglobulins by routine immunofluorescence but stained for IgG+λ by paraffin immunofluorescence after pronase digestion. RNA-based immunoglobulin repertoire sequencing performed on bone marrow aspirate identified an IgGλ (γ1) clone, which was highly atypical, combining an extensively mutated (23.6%) Ig heavy chain derived from the IGHV1-24 with low pI and unusual mutations and a light chain derived from an extremely rare germline gene (IGLV10-54). This report expands the pathologic spectrum of MIg crystalline nephropathies by describing a unique case of crystalline nephropathy with IgGλ deposits manifesting as membranous nephropathy.

Recurrent atypical antiglomerular basement membrane nephritis in the kidney transplant.

Atypical antiglomerular basement membrane (anti-GBM) nephritis can be defined as linear GBM staining for monotypic or polytypic immunoglobulin (Ig) by immunofluorescence (IF) without a diffuse crescentic pattern. We describe the clinicopathologic features of 6 patients (18 biopsies) in this first series of recurrent atypical anti-GBM nephritis after kidney transplantation. Recurrent glomerulonephritis occurred at a mean of 3.8 months posttransplant (range 1-7 months). Three index biopsies were for clinical indication, and 3 were protocol biopsies. Glomerular histologic changes were mild, with 2 showing segmental endocapillary hypercellularity, 1 focal glomerular microangiopathy, and the others no significant glomerular histologic changes. All 6 allografts showed monotypic linear glomerular Ig staining by IF: IgG kappa (n = 2), IgG lambda, IgA kappa, IgA lambda, and IgM lambda. Follow-up biopsies were available for 5 patients and showed similar histologic and IF findings without evidence of significant progression. No patients had detectable serum anti-GBM antibody or monoclonal proteins. The mean serum creatinine level on follow-up (24-62 months posttransplant) was 1.8 (range 0.93-2.77) mg/dL; no grafts were lost to recurrent disease. This series demonstrates that monotypic atypical anti-GBM recurs in the allograft and supports the idea that this disease is due to a circulating monoclonal protein.

Infection related membranoproliferative glomerulonephritis secondary to anaplasmosis: A case report.

BACKGROUND: Anaplasmosis is a tick-borne disease with a range of clinical manifestations, from a flu-like illness with fever and myalgias to a severe systemic disease with multisystem organ failure. Although renal involvement is not a common presentation, there have been few cases reporting acute kidney injury from Anaplasmosis. CASE SUMMARY: We present a 55-year-old female with anaplasmosis who developed acute kidney injury due to membranoproliferative glomerulonephritis (MPGN). The patient originally presented with cough and shortness of breath. She was admitted to the hospital with a diagnosis of community acquired pneumonia and received antibiotics. During the hospital course she developed severe acute renal failure. Initial serological work up didn't provide any conclusive diagnosis. Hence, she underwent kidney biopsy which showed MPGN pattern suggesting autoimmune, multiple myeloma or infectious etiology. Extensive work up was undertaken which was negative for autoimmune diseases, vasculitis panel, paraproteinemias but tested positive for IgG anaplasma with high titers indicating Anaplasmosis. CONCLUSION: Our case shows a unique presentation of severe acute renal failure from MPGN from tick borne illness. MPGN is usually seen with autoimmune diseases, hepatitis C virus infections, paraproteinemias. Hence, we suggest that tick borne illness should also be considered when evaluating acute renal failure cases in tick borne prevalent regions.

A Unique Endoscopic Presentation of Colon Metastases From Primary Invasive Lobular Carcinoma of the Breast.

Breast cancer is the leading cause of female malignancy-associated death worldwide. The most common sites of metastases are the lung, liver, brain, and skeleton. A 68-year-old female with invasive lobular carcinoma metastatic to the axial skeleton was found to have new skin and colonic metastases discovered on serial surveillance positron emission tomography-computed tomography scans. The colonic metastases did not present with any gastrointestinal symptoms and did not form exophytic masses, which are typically associated. Instead, her colonic metastases presented as unusual diaphragm-like strictures within the left colon discovered on endoscopy, which is a relatively rare phenomenon. This case raises awareness of and elucidates new manners of presentation of metastatic invasive lobular carcinoma within the colon.

Recognizing a Mediastinal Mass: A Case of Primary Mediastinal Large B-Cell Lymphoma With Pruritus in a 23-Year-Old Adult Male Sailor.

Primary mediastinal large B-cell lymphoma (PMBCL) is a rare, non-Hodgkin, B-cell lymphoma thought to originate from thymic B cells, which occurs primarily in young adults such as in the active duty population. Primary mediastinal large B-cell lymphoma (PMBCL) presents as a large mediastinal mass, posing risks to the cardiopulmonary safety of patients and challenging the routine approach to diagnosis. We describe a case of a 23-year-old male sailor who presented to sick call on his ship while in port with shortness of breath, night sweats, 50-pound weight loss, and pruritic punched-out lesions on all extremities. An initial chest X-ray showed a large consolidation. After being seen in the pulmonary medicine clinic 5 weeks after his initial presentation, the patient was admitted to the intensive care unit after computed tomography of his chest revealed a mediastinal mass, causing compression of both the right bronchus and superior vena cava with a large pericardial effusion. Empiric high-dose dexamethasone was initiated before a formal diagnosis due to his significant risk for cardiopulmonary compromise. Following diagnosis and two cycles of chemotherapy, the patient was transferred to a medical oncology facility in the continental USA. This case demonstrates the need to educate all military providers to recognize the presentation of mediastinal masses in active duty service members and the importance of urgently escalating these patients to higher levels of care in order to avoid life-threatening complications.

A Rare Coexistence of Seminoma and Hodgkin's Lymphoma in Hawai'i.

Both Hodgkin's lymphoma and testicular cancers can present in young men; however, concurrent Hodgkin's lymphoma with seminoma is very rare. When they do coexist, careful consideration must be made to avoid missing new cancer by assuming the presence of primary metastatic disease when lymphadenopathy presents. Here we present a rare case of coexistence of seminoma and Hodgkin's lymphoma and the staging and treatment challenges associated with a 2-cancer diagnosis.

Nodular Vascular Transformation of the Lymph Node Sinuses Mimicking Sarcomatoid Change in Renal Cell Carcinoma: A Potential Diagnostic Pitfall.

Vascular transformation of the lymph node sinuses (VTS) is an uncommon phenomenon that is believed to occur secondary to obstruction of efferent lymphatics, frequently occuring in retroperitoneal lymph nodes draining cancer. The nodular subtype of VTS, in particular, can mimic metastatic cancer, such as metastatic renal cell carcinoma with sarcomatoid differentiation, potentially resulting in inaccurate tumor grading and/or staging. We present a case of nodular VTS mimicking metastatic renal cell carcinoma with sarcomatoid differentiation in a patient with high-grade clear cell renal cell carcinoma, and explore the relevant differential diagnosis. Awareness of VTS is essential to avoid misdiagnosis of this benign and curative condition.