Crystal-Storing Histiocytosis in Bone Marrow: A Clinicopathologic Study of Eight Cases and Review of the Literature

Cutaneous crystal storing histiocytosis: A case series with review of literature

Crystal-storing histiocytosis (CSH) is a rare condition in which crystals accumulate in the cytoplasm of histiocytes and is usually associated with a lymphoplasmacytic neoplasm. Cutaneous CSH is extraordinarily rare and limited to case reports in the literature. We report two cases of this disease with cutaneous involvement. Case 1 was a 65-year-old male with a 4-month history of a pruritic eruption that started as a solitary pink to skin-colored indurated plaque on the anterior neck before progressing to involve the whole neck, chest wall, and face. Case 2 was a 54-year-old woman with a history of unspecified "lymphoma" who presented with a soft nodule on the forearm. Biopsies from both cases had similar findings and showed a proliferation of epithelioid cells with pink cytoplasm and intracellular crystalline structures infiltrating the dermis and subcutaneous fat. In the first case, the cells were positive for CD43, CD45, CD68, and IgG kappa, and in the second case, the crystals were positive for IgG lambda. Based on these findings, the patients were diagnosed with cutaneous CSH. We highlight this rare diagnosis and the importance of investigating an underlying lymphoplasmacytic neoplasm.

Combined crystal-storing histiocytosis, light chain proximal tubulopathy, and light chain crystalline podocytopathy in a patient with multiple myeloma: a case report and literature review

BACKGROUND

Crystal-storing histiocytosis (CSH), light chain proximal tubulopathy (LCPT), and light chain crystalline podocytopathy (LCCP) are rare complications of multiple myeloma (MM) or monoclonal gammopathy of renal significance, and their diagnoses are challenging.

CASE PRESENTATION

In this case, a 69-year-old Chinese woman presented with suspicious Fanconi syndrome with renal insufficiency. Immunofixation electrophoresis of both serum and urine revealed elevated immunoglobulin G kappa (IgGkappa) and kappa light chain. Bone marrow aspirate revealed 15% plasma cells with considerable cytoplasmic granular inclusions and needle-shaped crystals. Renal biopsy confirmed the final pathologic diagnosis of kappa-restricted CSH, combined LCPT and LCCP by immunoelectron microscopy. A number of special casts were present which could easily be misdiagnosed as light chain cast nephropathy. Immunofluorescence on frozen tissue presented false negative for kappa light chain, as ultimately proven by paraffin-embedded tissue after pronase digestion. MM and CSH were diagnosed, and two cycles of chemotherapy were given. The patient subsequently refused further chemotherapy, and her renal function remained relatively stable during a 2.5-year follow-up period.

CONCLUSIONS

In conclusion, we report a rare case of generalized kappa-restricted CSH involving bone marrow and kidney, combined with LCPT and LCCP, provide a comprehensive summary of renal CSH, and propose a new nomenclature of monoclonal immunoglobulin-induced crystalline nephrology. The presentation of monoclonal immunoglobulin and Fanconi syndrome should suggest the presence of monoclonal immunoglobulin-induced crystalline nephrology. Use of paraffin-embedded tissue after pronase digestion and immunoelectron microscopy is beneficial to improve the sensitivity of diagnosis.

Crystal-Storing Histiocytosis: The Iceberg of More Serious Conditions

Crystal-storing histiocytosis is a rare condition that is histologically characterized by intracellular cytoplasmic crystalline inclusions. It usually presents monoclonal immunoglobulins that deposit within histiocytes, which accumulate and affect different organs of the human body and are commonly associated with lymphoproliferative conditions, especially those with plasmacytic differentiation. The prognosis of this condition is variable and related to the underlying clinical disease. In this review article, we aim to describe and discuss the clinical and pathological characteristics of crystal-storing histiocytosis based on the available literature and to provide a thorough differential diagnosis.

Crystal-storing histiocytosis in the stomach: A case report and review of the literature

Crystal-storing histiocytosis (CSH) is a rare disorder characterized by the accumulation of non-neoplastic histiocytes that contain intracytoplasmic crystallized immunoglobulins. Although CSH can occur in various organs, gastric CSH is very rare. Therefore, diagnosing gastric CSH remains a challenge. Here, we present the case of a 69-year-old man with localized gastric CSH who presented with positive fecal occult blood for 2 days. Gastroscopy showed that there was a piece of irregular whitish focus in the big bend of the gastric antrum, which was soft and elastic. Histologically, the biopsied gastric mucosa showed chronic inflammation, mild activity with erosion, and numerous eosinophilic mononuclear cells containing fibrillary crystalloid inclusions in the lamina propria. Immunohistochemically, these crystal-containing cells were positive for CD68/PGM1 and Igk, which revealed that the cells were histiocytes harboring kappa light chain-restricted immunoglobulin crystals. Electron microscopic examination showed numerous high-electron-density particles in the cytoplasm of cells, with crystal structures of different sizes and shapes. This case highlights how immunohistochemistry can help with differential diagnosis and classification.

F-18 Fluorodeoxyglucose PET/CT as a Diagnostic Tool in Orbital Inflammatory Disorders

PURPOSE

To assess the usefulness of FDG-PET/CT as a potential diagnostic tool for detecting underlying systemic diseases (SD) in patients with orbital inflammatory disorders (OID).

METHODS

All consecutive patients managed for new-onset OID between 2011 and 2018 in a tertiary referral center, who underwent FDG-PET/CT as part of the etiological diagnostic workup were evaluated. To quantify the incremental value of FDG-PET/CT over standard diagnostic workup, the Net Reclassification Index (NRI) and Integrated Discrimination Index (IDI) were used.

RESULTS

Among the 22 patients enrolled, 11 (50%) had a positive FDG-PET/CT. After clinicobiological evaluation, FDG-PET/CT correctly reclassified 4(29%) of 14 patients with SD (p = .04) and 1(13%) of 8 with idiopathic orbital inflammation syndrome (p = .32). NRI and IDI were 0.41 ± 0.17 (p = .03) and 0.38 ± 0.08 (p < .001), respectively. FDG-PET/CT successfully detected asymptomatic lesions in all (n = 4) patients with lymphoma.

CONCLUSION

FDG-PET/CT enabled accurate reclassification of more than one-quarter of patients with SD, especially extraorbital lymphomas.

New Kids on the Block

CONTEXT.—

With the increasing development and use of iatrogenic agents, pathologists are encountering more novel foreign materials in retrieved gastrointestinal specimens. These colorful and unusual-appearing foreign materials can pose a diagnostic dilemma to those unaware of their morphology, especially if the relevant clinical history is lacking.

OBJECTIVE.—

To discuss the histopathologic features, clinical scenarios and significance, and differential diagnosis of relatively recently described, yet quickly expanding, family of iatrogenic agents that can present as foreign materials in gastrointestinal specimens-pharmaceutical fillers (crospovidone and microcrystalline cellulose), submucosal lifting agents (Eleview and ORISE), lanthanum carbonate, hydrophilic polymers, OsmoPrep, yttrium 90 microspheres (SIR-Sphere and TheraSphere), and resins (sodium polystyrene sulfonate, sevelamer, and bile acid sequestrants).

DATA SOURCES.—

We collate the findings of published literature, including recently published research papers, and authors' personal experiences from clinical sign-out and consult cases.

CONCLUSIONS.—

Correct identification of these iatrogenic agents is important because the presence of some novel agents can explain the histopathologic findings seen in the background specimen, and specific novel agents can serve as diagnostic clues to prompt the pathologist to consider other important and related diagnoses. Awareness of even biologically inert agents is important for accurate diagnosis and to avoid unnecessary and expensive diagnostic studies.

Combined renal proximal tubulopathy and crystal storing histiocytosis in a patient with κ light chain multiple myeloma

Multiple myeloma accounts for 10-15% of all hematologic malignancies, and 20% of deaths related to cancers of the blood and bone marrow. Diagnosis is defined by the presence of a serum monoclonal spike (M-spike) of more than 3 g/dL or more than 10% clonal plasma cells in the bone marrow and at least one myeloma-defining event, such as hypercalcemia, anemia, bone lesions, or renal impairment. The kidney is a major target organ, and renal impairment is frequently the first manifestation of the disease. Renal damage occurs in up to 40% of patients and 10-20% will require dialysis. Monoclonal immunoglobulin light chains are the major causes of renal complications in multiple myeloma. Glomerular disease, with the deposition of monoclonal immunoglobulins or their components, includes monoclonal immunoglobulin deposition disease, AL or AH amyloidosis, type I cryoglobulinemia, proliferative glomerulonephritis with monoclonal IgG deposits, immunotactoid glomerulopathy, and fibrillary glomerulonephritis. In addition, tubulointerstitial diseases with the deposition of monoclonal immunoglobulins or their components, are constituted by light chain cast nephropathy, light chain proximal tubulopathy, and crystal-storing histiocytosis.

We report the case of a 66-year-old woman who presented with albumin-predominant moderate proteinuria and renal failure. Serum and urine immunofixation electrophoresis showed monoclonal κ light chain in both. Renal biopsy confirmed κ-restricted crystal-storing renal disease involving proximal tubular epithelial cells and crystal storing histiocytosis. Multiple myeloma with crystal storing histiocytosis was discovered in bone marrow biopsy. Thus, we present an unusual case of a myeloma patient presenting light chain proximal tubulopathy and crystal-storing histiocytosis both in the kidney and in the bone marrow.

Crystal-storing histiocytes in ascites leading to a diagnosis of plasma cell myeloma

Histiocytes containing multiple needle-shaped eosinophilic crystals visualized in a peritoneal fluid sample during evaluation of a patient for liver transplantation led to the diagnosis of unsuspected IgA kappa myeloma. Crystal-storing histiocytosis is a rare phenomenon typically associated with multiple myeloma and B-cell lymphoproliferative disorders. It can involve almost any anatomic site and can occasionally be seen in body fluid samples.

Immunoglobulin-Storing Histiocytosis: A Case Based Systemic Review

Crystal-storing histiocytosis (CSH) is a rare event in disorders associated with monoclonal gammopathy and is mostly associated with the accumulation of immunoglobulins (Igs) in the cytoplasm of histiocytes. In this article, we present a case of a 75-year-old female with IgG kappa monoclonal gammopathy of undetermined significance (MGUS) and signs of a non-crystallized version of immunoglobulin-storing histiocytosis (IgSH) in a vertebra corpus. Furthermore, we performed a literature review based on all cases of storing histiocytosis identified by literature search between 1987 and 2020 and identified 140 cases in total. The median age at diagnosis was 60 years (range 18–91), with an equal sex distribution (51% men). The majority of the patients had an underlying neoplastic B-cell disorder, most often multiple myeloma (MM), MGUS, or lymphoplasmacytic lymphoma (LPL). The main affected organ systems or tissue sites were bone (n = 52), followed by head and neck (n = 31), kidney (n = 23), lung (n = 20), and gastrointestinal (GI)-tract (n = 18). IgG was the main immunoglobulin class involved, and most cases were associated with kappa light chain expression. We conclude that IgSH is a rare disease entity but should be considered with unusual findings in several organ systems associated with monoclonal gammopathy, especially with kappa light chain expression.

Gastric crystal-storing histiocytosis with concomitant mucosa-associated lymphoid tissue lymphoma

Crystal-storing histiocytosis (CSH) is a rare entity that is characterized by intrahistiocytic accumulation of crystallized immunoglobulins. CSH is not a malignant process per se, but the majority of CSH cases are associated with underlying lymphoproliferative disorder. Although CSH can occur in a variety of organs, gastric CSH is very rare. We present a localized gastric CSH with concomitant mucosaassociated lymphoid tissue (MALT) lymphoma, manifesting as an ulcer bleeding in a 56-year-old man. Histologically, the biopsied gastric mucosa demonstrated expansion of the lamina propria by prominent collections of large eosinophilic mononuclear cells containing fibrillary crystalloid inclusions. Immunohistochemical studies revealed that the crystal-storing cells were histiocytes harboring kappa light chain-restricted immunoglobulin crystals. Within the lesion, atypical centrocyte-like cells forming lymphoepithelial lesions were seen, consistent with MALT lymphoma. Since this entity is rare and unfamiliar, difficulties in diagnosis may arise. Particularly, in this case, the lymphomatous area was obscured by florid CSH, making the diagnosis more challenging.

An update to the pathogenesis for monoclonal gammopathy of renal significance

Monoclonal gammopathy of renal significance (MGRS) is characterized by the nephrotoxic monoclonal immunoglobulin (MIg) secreted by an otherwise asymptomatic or indolent B-cell or plasma cell clone, without hematologic criteria for treatment. The spectrum of MGRS-associated disorders is wide, including non-organized deposits or inclusions such as C3 glomerulopathy with monoclonal glomerulopathy (MIg-C3G), monoclonal immunoglobulin deposition disease, proliferative glomerulonephritis with monoclonal immunoglobulin deposits and organized deposits like immunoglobulin related amyloidosis, type I and type II cryoglobulinaemic glomerulonephritis, light chain proximal tubulopathy, and so on. Kidney biopsy should be conducted to identify the exact disease associated with MGRS. These MGRS-associated diseases can involve one or more renal compartments, including glomeruli, tubules and vessels. Hydrophobic residues replacement, N-glycosylated, increase in isoelectric point in MIg causes it to transform from soluble form to tissue deposition, causing glomerular damage. Complement deposition is found in MIg-C3G, which is caused by an abnormality of the alternative pathway and may involve multiple factors including complement component 3 nephritic factor, anti-complement factor auto-antibodies or MIg which directly cleaves C3. The effect of transforming growth factor beta and platelet-derived growth factor-β on mesangial extracellular matrix is associated with glomerular and tubular basement membrane thickening, nodular glomerulosclerosis, and interstitial fibrosis. Furthermore, inflammatory factors, growth factors and virus infection may play an important role in the development of the diseases. In this review, for the first time, we discussed current highlights in the mechanism of MGRS-related lesions.

An update to the pathogenesis for monoclonal gammopathy of renal significance

Monoclonal gammopathy of renal significance (MGRS) is characterized by the nephrotoxic monoclonal immunoglobulin secreted by an otherwise asymptomatic or indolent B cell or plasma cell clone, without hematologic criteria for treatment. These MGRS-associated diseases can involve one or more renal compartments, including glomeruli, tubules, and vessels. Hydrophobic residue replacement, N-glycosylated, increase in isoelectric point in monoclonal immunoglobulin (MIg) causes it to transform from soluble form to tissue deposition, and consequently resulting in glomerular damage. In addition to MIg deposition, complement deposition is also found in C3 glomerulopathy with monoclonal glomerulopathy, which is caused by an abnormality of the alternative pathway and may involve multiple factors including complement component 3 nephritic factor, anti-complement factor auto-antibodies, or MIg which directly cleaves C3. Furthermore, inflammatory factors, growth factors, and virus infection may also participate in the development of the diseases. In this review, for the first time, we discussed current highlights in the mechanism of MGRS-related lesions.

Intrahepatocellular crystal storing mimicking a clinical liver disease during monoclonal gammopathy: report of a case and review of the literature

We present an unusual case of liver involvement in monoclonal gammopathy with generalized crystal-storing histiocytosis (G-CSH).A bone marrow storage disease was diagnosed in a 79-year-old man with monoclonal gammopathy of uncertain significance (MGUS). The patient presented with pleural effusion, an osteolytic lesion of the humerus, and an increase of aspartate transaminase and cholestatic markers that raised the clinical suspect of liver disease. A second bone marrow biopsy confirmed the diagnosis of MGUS with a histiocytic component suggestive for G-CSH.Liver biopsy showed an unremarkable histology, no significant inflammatory infiltrates, and intrasinusoidal foamy histiocytes. PAS and Masson's trichrome stains, showed, in the cytoplasm of both histiocytes and hepatocytes, rod-shaped eosinophilic crystals, which were immunoreactive for kappa light chains. Transmission electron microscopy performed on reprocessed histological sections confirmed the presence of crystals in the hepatocyte cytoplasms. Immunogold labeling intensely stained crystals for kappa light chains.To the best of our knowledge, this is the second case in which an intrahepatocellular crystal storage is described during liver involvement in G-CSH. The present case also suggests that an increase in liver serum enzymes may support the clinical diagnosis of liver CSH in a patient with MGUS.

Crystal-storing Histiocytosis in the Stomach: A Clue to Subtle Hematolymphoid Malignancies

Crystal-storing histiocytosis (CSH) is an under-recognized entity with a striking association with lymphoproliferative disorders. To study the typical morphologic features of gastric CSH, all lymphomas diagnosed on in-house gastric specimens at The Ohio State University between January 1, 2008 and January 1, 2017 were retrieved. This search yielded 66 specimens from 51 unique patients. All cases were reviewed with CSH identified in 7 stomach biopsies from 4 patients (2 men:2 women; average age, 69 y; range, 56 to 82 y). Endoscopic findings were all abnormal: diffuse nodularity and white discoloration (n=1), patchy nodularity (n=1), and malignant-appearing fundic mass with lymphadenopathy (n=2). We report the typical gastric CSH lesion displays full-thickness expansion of the lamina propria by a lymphohistiocytic infiltrate that distorts the usual gastric glandular architecture. On high power, all cases were defined by the presence of macrophages with abundant eosinophilic cytoplasm containing nonrefractile, nonpolarizable fibrillary cytoplasmic inclusions. Three of the 4 patients had a kappa-restricted lymphoma; the 1 patient with a lambda-restricted lymphoma had the fewest macrophages. Follow-up data were available up to 228 weeks. All 4 patients had persistent/recurrent lymphoma, and 2 patients died of lymphoma-related complications. None of the CSH cases were prospectively recognized as CSH, and 1 case was initially misdiagnosed as a xanthoma. In summary, CSH is an under-recognized lesion historically associated with lymphoproliferative disorders and we found associated with a high mortality in this small series. Since CSH can be so florid as to obscure the concomitant lymphoma, awareness is crucial for accurate diagnosis.

Generalized crystal-storing histiocytosis with diffuse large B-cell lymphoma and monoclonal gammopathy in a Chinese elderly woman: a case report

BACKGROUND

Crystal-storing histiocytosis (CSH) is a rare lesion characterized by sheets of crystal-laden non-neoplastic histiocytes. CSH shows a prominent association with lymphoproliferative disorders that express monoclonal immunoglobulins, mainly multiple myeloma (MM), lymphoplasmacytic lymphoma (LPL) and monoclonal gammopathy of undetermined significance (MGUS). However, no aggressive B cell lymphoma has been reported to be associated with CSH.

CASE PRESENTATION

A 74-year-old Chinese woman presented with multiple subcutaneous masses, abdominal pain, and fever. An IgM kappa type of monoclonal gammopathy (MG) was noted by immunofixation performed on the patient's serum. Computed tomographic (CT) scan revealed subcutaneous masses on the left upper arm and at the waist and multiple low-density lesions in the spleen. Microscopically, sections of subcutaneous masses revealed sheets of large polygonal and spindle cells with abundant eosinophilic cytoplasm, round to ovoid eccentric nuclei, reticulate chromatin, and median nucleoli. Massive needle-shaped crystals were confined to the cytoplasm. Immunohistochemically, these crystal-containing cells were positive for CD68/PGM1, CD163, IgM, and Igκ. Meanwhile, the splenic tumour was diagnosed as diffuse large B-cell lymphoma (DLBCL), non-germinal-centre B (non-GCB) subtype (Hans algorithm). Immunohistochemistry for IgM was positive in the cytoplasm of some neoplastic cells. Immunoglobulin heavy chain (IgH) gene rearrangement was detected by PCR analysis of the subcutaneous mass and the splenic tumour.

CONCLUSION

To the best of our knowledge, this is the first case of generalized CSH with DLBCL and MG. Although the rarity of CSH and separate locations of CSH and lymphoma led to a diagnostic dilemma, the presence of MG was a clue to appreciate the relation between CSH and DLBCL. This case stressed a full investigation into the underlying lymphoproliferative disorder for integrated diagnosis and correct treatments.

Massive generalized crystal-storing histiocytosis associated with extracellular crystalline nephropathy: clinical, immunohistochemical, and ultrastructural studies of a unique disorder and review of the literature

Crystal-storing histiocytosis (CSH) is a rare disorder characterized by the accumulation of nonneoplastic histiocytes containing intracytoplasmic crystallized immunoglobulins. In most cases, there is an associated underlying lymphoplasmacytic neoplasm expressing Ig kappa light chain. About 131 cases of CSH have been identified. There is a localized and a generalized form of CSH and it can involve several sites including bone marrow, lungs, lymph nodes, liver, spleen, gastrointestinal tract, and kidney. Generalized CSH is less frequent and involves multiple organs and tends to have a worst prognosis than localized CSH. Around 20 cases of renal involvement in CSH have been reported so far. Paraprotein-induced crystalline nephropathy can be divided into two categories based on whether the crystals in the kidney are intracellular (including light chain proximal tubulopathy with crystals and CSH) or extracellular (including the crystalline variant of myeloma cast nephropathy and crystalglobulin-induced nephropathy). The former tends to present with slowly worsening kidney dysfunction and generally has a good prognosis, whereas the latter usually presents with rapidly progressive renal failure and is associated with poor renal outcome. We present a case of generalized CSH associated with extracellular crystalline nephropathy with a fulminant and fatal clinical course. Kappa light-chain crystals were found exclusively extracellularly within the tubular lumen, not within the tubular epithelial cells nor the histiocytes, and the massive presence of those precipitates led to the acute renal failure. Consequently, we review the renal involvement in CSH in the literature and discuss the unique mechanism of renal injury in this case.