Amyloidosis and multiple myeloma. A reevaluation using a control population

Two kinds of rare light chain cast nephropathy caused by multiple myeloma: case reports and literature review

BACKGROUND

Light chain cast nephropathy (LCCN) is the most common renal disease caused by multiple myeloma (MM). In addition to ordinary light chain protein casts, there are a few rare casts with unique shapes, including light chain amyloid casts (LCAC) and light chain crystal casts (LCCC).

CASE PRESENTATIONS

Here, we report two patients. Patient 1 is a 72-year-old man who was clinically diagnosed with MM and acute kidney injury (AKI). Pathological examination of a renal biopsy revealed that there were many amyloid casts in the distal tubules that had a lightly-stained central area and a deeply-stained burr-like edge. The marginal zone of the cast was positive for Congo red staining and contained numerous amyloid fibers, as observed by electron microscopy. No systemic amyloidosis was found. The patient received 4 courses of bortezomib-based chemotherapy, and then, his MM achieved partial remission. Patient 2 is a 57-year-old man who was also clinically diagnosed with MM and AKI. Pathological examination of a renal biopsy showed that there were many crystalline casts in the distal tubules that were fully or partially composed of crystals with different shapes, including rhomboid, needle, triangle, rectangle and other geometric shapes. Congo red staining was negative. Crystals were also detected in the urine of this patient. After 9 courses of treatment with a bortezomib-based regimen, his MM obtained complete remission and his renal function returned to normal.

CONCLUSIONS

LCAC and LCCC nephropathy caused by MM are two rare types of LCCN, and both have their own unique morphological manifestations. LCAC nephropathy may not be accompanied by systemic amyloidosis. The diagnosis of these two unique LCCNs must rely on renal biopsy pathology, and the discovery of urine crystals is of great significance for indicating LCCC nephropathy.

Origins of a pervasive, erroneous idea: The "green birefringence" of Congo red-stained amyloid

Congo red was discovered to stain amyloid by accident in 1922, and Congo red-stained amyloid was shown to be birefringent on polarization microscopy in 1927. Colours, namely green and yellow, were reported under these conditions in 1945, although these are only two of various anomalous colours that may be seen, depending on the optical set-up. In 1953 there began a dogmatic insistence that in Congo red-stained amyloid between crossed polarizer and analyser green alone should be seen, and the finding of any other colour was a mistake. The idea that green, and only green, is essential for the diagnosis of amyloid has persisted almost universally, and virtually all mentions of Congo red-stained amyloid say that it just shows "green birefringence" or "apple-green birefringence." This idea is wrong and is contrary to everyday experience, because green is seldom seen on its own under these conditions of microscopy, and often, there is no green at all. How observers maintain this unscientific position is explained by a study of its historical origins. Most of the early literature was in German or French and was usually quoted in English at second hand, which meant that misquotations, misattributions and misunderstandings were common. Few workers reported their findings accurately, hardly any attempted to explain them, and until 2008, none gave a completely satisfactory account of the physical optics. The history of Congo red-stained amyloid is an instructive example of how an erroneous belief can become widely established even when it is contradicted by simple experience.

Intratubular amyloid in light chain cast nephropathy is a risk factor for systemic light chain amyloidosis

Light chain cast nephropathy is the most common form of kidney disease in patients with multiple myeloma. Light chain casts may occasionally show amyloid staining properties, that is, green birefringence after Congo red staining. The frequency and clinical significance of this intratubular amyloid are poorly understood. Here, we retrospectively assessed the clinicopathological features of 60 patients with histologically proven light chain cast nephropathy with a specific emphasis on intratubular amyloid, especially, its association with extrarenal systemic light chain amyloidosis. We found intratubular amyloid in 17 cases (17/60, 28%) and it was more frequent in patients with λ light chain gammopathy (13/17 in the 'intratubular amyloid' group vs 19/43 in the 'no intratubular amyloid' group, P=0.02). Pathological examination of extrarenal specimens showed that intratubular amyloid was significantly associated with the occurrence of systemic light chain amyloidosis (5/13 in the 'intratubular amyloid' group vs 0/30 in the 'no intratubular amyloid' group, P=0.001). Our results indicate that first, intratubular amyloid is not a rare finding in kidney biopsies of patients with light chain cast nephropathy, and, second, it reflects an amyloidogenic capacity of light chains that can manifest as systemic light chain amyloidosis. Thus, intratubular amyloid should be systematically screened for in kidney biopsies from patients with light chain cast nephropathy and, if detected, should prompt a work-up for associated systemic light chain amyloidosis.

Myélome à chaînes légères révélé par une arthropathie amyloïde. À propos de deux observations

INTRODUCTION

Amyloid arthropathy occurs in 5-15% of patients with multiple myeloma. It is rarely inaugural. Some cases are reported in which the articular manifestations are present many months before the diagnosis of myeloma. We report two unusual cases where the amyloid arthropathy reveals the multiple myeloma.

EXEGESIS

Case 1: A 54-year-old man take medical advice for a polyarthritis evolving for 6 months. He has no evidence of multiple myeloma except a hypercalcemia and a hypoalbuminemia. The diagnosis of multiple myeloma is based on an immunobinding of plasmatic proteins. It is a light chain multiple myeloma, lambda type. Amylosis is revealed by biopsy specimens from the synovial tissue of the knee. The patient died rapidly because of an intestinal hemorrhage. Case 2: A 78-year-old woman complains from a polyarthritis evolving for 4 months. She has besides an elevated erythrocyte sedimentation rate, an anemia and a renal insufficiency, a profound hypogammaglobulinemia. There is no radiological abnormalities. The diagnosis of multiple myeloma is based on serum and urine immunoelectrophoresis. It is a light chain multiple myeloma, lambda type. The patient is at her sixth monthly course of cyclophosphamid and prednisone. As far as amyloid arthropathy is concerned, it is relatively improved by corticoid intra-articular injections.

CONCLUSION

These are two case reports of a light chain multiple myeloma of lambda type, associated to an amyloid arthropathy in its polyarticular presentation, mimicking a rheumatoïd arthritis. The revelatory nature of the amyloid arthropathy is interesting to report.

Multiple myeloma and amyloidosis of the tongue

Tongue biopsies of 30 diagnosed cases of multiple myeloma were examined light and electron microscopically and amyloid deposits were identified in 8 patients. Immunochemical typing of amyloid in kappa and lambda subtypes was performed successfully although positive staining of tissue-associated immunoglobulin light chains made reliable identification of amyloid with this technique difficult. Cells of macrophage lineage appear to play a central role in light chain-associated amyloidogenesis. Our findings do not agree with the reported higher amyloidogenic potential of lambda light chains and we were unable to show a positive correlation between the percentage plasma cells in bone marrow aspirates or the presence of urinary light chains and myeloma-associated amyloidosis.

Multiple myeloma presenting with extensive oral and perioral amyloidosis

The case of a young adult patient, with a kappa-light-chain-secreting multiple myeloma and extensive oral and salivary gland amyloid deposits, is presented. This case illustrates the necessity of a multidisciplinary approach using biochemical, radiographic, and relevant histologic investigations in the diagnosis of multiple myeloma. Factors influencing the prognosis of this neoplastic condition are discussed. Microscopic examination of the oral amyloid deposits supports the suggested central role played by the macrophage in amyloidogenesis.

Amyloid casts within renal tubules: a singular finding in myelomatosis

This study was carried out in order to investigate a possible relationship between multiple myeloma and the occurrence of material exhibiting the properties of amyloid within renal tubules. Two groups of autopsied patients, with myelomatosis and benign monoclonal gammopathy were examined for the presence of amyloid deposits in renal and extra-renal sites. Urines were analysed for the presence and amount of Bence Jones protein and the pattern of the associated proteinuria was characterized. Renal tubular casts exhibiting the histochemical characteristics of immuno-amyloid were found exclusively in myeloma patients with Bence Jones proteinuria but without the renal lesions classically described as "myeloma kidney". This finding was independent of the occurrence of immuno-amyloid deposits in other renal and extra-renal sites, suggesting involvement of local factors in the pathogenesis of amyloid formation and deposition within renal tubular lumina. The results of present study suggest the conclusion that the presence of amyloid intratubular casts is to be regarded as a peculiar finding in myelomatosis.

Renal manifestations of extrarenal neoplasms

In a study of 1270 consecutive autopsies there were 314 patients with malignant neoplasms arising in sites other than the kidney and central nervous system. In over 50 per cent of these there was significant renal damage related to cancer. Renal damage was produced by direct involvement of one or both kidneys by the neoplasm or by indirect effects. The latter included ischemic damage, metabolic injury, immunologic injury, and effects of therapy directed at the malignant tumor. In patients with cancer, tumor bulk and invasion of vital organs do not always explain the clinical deterioration and cause of death. Recognition of the indirect effects of tumors on the kidney and other organ systems is essential to the understanding of the generalized host response to malignant disease.

Amyloidosis in Malaysian aborigines (Orang Asli)

Material from 334 consecutive autopsies on Orang Asli subjects performed in the University Hospital, Kuala Lumpur between May 1967 and June 1978 was examined for amyloidosis. Nine positive cases were found, all in patients above 40 years of age, giving an age-corrected incidence of about 9%. In 6 cases, amyloidosis was probably secondary to tuberculosis. The remaining 3 cases exhibited a pericollagenous distribution characteristic of primary amyloidosis. Involvement of the heart and lungs was prominent. However, there were considerable similarities in the distribution and staining properties of the amyloid in the 2 groups. Though both the heart and kidney were frequently affected, the kidney was the most common organ to give rise to clinical symptoms. Infection probably plays a major contributory role in amyloidosis in the Orang Asli.

The origin of multinucleate giant cells in myeloma kidney from mononuclear phagocytes: an ultrastructural study

Ultrastructural examination of a biopsy of a myeloma kidney has shown structural relationships between the multinucleate giant cells which characterize this condition and macrophage polykarya. On the other hand, no evidence was found of any resemblance to renal tubular cells. Moreover the electron microscopic observations indicate that these multinucleate giant cells, in common with the mononuclear phagocytes, attempt to ingest the cast material which in addition becomes fibrillar in the zones of endocytosis. No such phenomena were observed in the vicinity of tubular cells. In conclusion the ultrastructural evidence suggests that the multinucleate giant cells of myeloma kidney are derived from mononuclear phagocytes.

Study of light-, electron- and immunofluorescence microscopy of urinary sediment in amyloidosis

Urinary sediment of 11 patients with amyloidosis and 12 without (with proteinuria or in good health) have been sutdied by different morphological techniques. By light microscopy, an amyloid-related substance was occasionally demonstrated both in patients with amyloidosis and in control subjects. Immunofluorescence (IF) showed substance A (amyloid component) to be present in some cases of amyloidosis and in controls. On electron-microscopy, fibrils with characteristic appearance of amyloid substance were found in some cases of amyloidosis (4 out of 11), but were also found in controls. It therefore seems difficult to establish the diagnosis of amyloidosis by microscopic studies of the urinary sediment.

Bone Marrow Amyloid in Patients with M-component

Amyloid substance was looked for in bone marrow aspirates of 28 patients presenting an M-component, in association with different illnesses (plasmocytoma, chronic lymphatic leukemia, lymphocytic lymphoma, « benign monoclonal gammapathy » and liver cirrhosis). Amyloid was detected in 12 out of 20 patients with plasmocytoma (60 %) and in 3 out of 8 patients with other illnesses (37.5%); it was found in 9 out of 13 cases (69.2%) presenting exclusive light chain production and in 6 out of 15 cases (40 %) with a monoclonal complete Ig. Lambda type light chain, either free or Ig-bound, was slightly more often (6 cases out of 10, 60 %) associated with amyloidosis than was K (9 cases out of 17, 52.9%). Bone marrow appeared to be more frequently involved than other sites considered elective such as rectal mucosa. Amyloid appeared as an intensively fluorescent substance present intercellularly in areas of variable number and size.

Amyloidosis and Light Chain Plasmocytoma

Nine cases of light chain plasmocytomas, 6 type λ and 3 type k, have been studied in reference to amyloid presence and localisation. Bone marrow plasmocytosis, light chains in serum and/or in the urine, and osteolytic lesions were demonstrated in all the patients. Initial symptoms, i.e., macroglossia and lymphadenopathy, were secondary to amyloid deposits in two patients; the absence of overt evidence of plasmocytoma had previously led to the diagnosis of « primary » amyloidosis in one case. Amyloidosis may therefore be associated with concealed plasmocytomas, evident only after a certain period of time. Amyloidosis was not detected in the sites where it was clinically suspected in two cases. However, on bone marrow aspirates, amyloid was present in seven patients where thioflavine T appeared as homogeneous, amorphous, intercellular substance localised in small areas.

Comprehensive study of humoral and cellular immune abnormalities in 26 patients with systemic amyloidosis

Serum immunoglobulin abnromalities in nonfamilial and systemic primary amyloidosis are distinct from those seen in multiple myeloma and more closely resemble those seen in benign monoclonal gammopathy. Surface lymphocyte characteristics also differentiate amyloid patients with or without monoclonal immunoglobulins from those with malignant B-cell dyscrasias. In vitro lymphocyte transformation with phytohemagglutinin and pokeweed mitogen is normal in amyloidosis, but T-cell function is significantly depressed in both primary and secondary amyloid disease as measured by concanavalin A responses.

The clinical spectrum of light chain myeloma. A study of 35 patients with special reference to the occurrence of amyloidosis

During a 40 month interval, 35 patients were seen with a plasma cell dyscrasia in which the only detectable monoclonal immunoglobulin abnormality consisted of excess production of either type kappa or type lambda light chains (Bence Jones protein). This group constituted 17.3 per cent of the total number of patients with plasma cell dyscrasias and 25.7 per cent of the patients with myeloma identified during the same period. Variable initial clinical presentation, the absence of a typical monoclonal serum spike and the unreliability of commonly used urine protein tests made recognition of the disorder difficult in many patients. Sulfosalicylic acid and p-toluene sulfonic acid proved valuable in screening for ueine protein. Definition of "proteinuria" by quantitative, electrophoretic and immunochemical studies was essential for diagnosis. Bence Jones proteinemia was present in 80 per cent of the patients; panhypogammaglobulinemia and lytic bone lesions were demonstrable in more than 60 per cent. Although no specific morphologic abnormality of marrow plasma cells was evident by light microscopy, the absence of rouleau on peripheral blood smear was a helpful diagnostic clue. Although patients with lambda light chains presented with more Bence Jones proteinuria, this did not correlate with the severity of initial renal functional impairment or with survival when compared to patients with kappa light chains. No other clinical or laboratory observation differentiated the groups with kappa light chains from those with lambda light chains. Amyloid was identified in seven patients. Their course was dominated by the features of primary systemic amyloidosis instead of the usual findings of classic myeloma. Patients with amyloidosis had lower initial serum albumin levels, fewer lytic bone lesions and reduced survival compared to patients without amyloidosis.

Multiple myeloma. A clinical review

This group of proliferative diseases of the plasma cell line, in which manifestations of abnormal immunoglobulin production are associated with variable degrees of depressed antibody synthesis, pose fascinating problems crossing many clinical and research disciplines. The present state of diagnosis and clinical management is assessed.

Amyloid in the aged heart: frequency and clinical significance

Cardiac amyloid accumulation is a common autopsy finding in elderly persons, the frequency increasing with each advancing age decade. In most cases the deposits are microscopic, confined to the atrial subendocardium, and of dubious significance. In a few cases, however, there is much more extensive cardiac involvement, with infiltration of the ventricular musculature and intracardiac conduction system. In the authors' recent autopsy study of 100 patients over 60 years of age, 10 had diffuse cardiac amyloidosis with biventricular involvement. Microscopically, the amyloid deposits often resembled foci of interstitial fibrosis. Significant cardiac enlargement (weight greater than 380 gm) was present in only 2 of these patients, and in only one of them were the clinical signs and symptoms clearly attributable attributable to the amyloid infiltration. It was difficult to assess the possible contribution of ventricular amyloid to congestive failure since most of the patients also had coronary arteriosclerosis. In the aged, clinically significant cardiac amyloidosis associated with cardiac enlargement appears to be part of a disease spectrum more commonly characterized by focal, clinically insignificant cardiac amyloid deposits. Yet several features suggest that senile cardiac amyloidosis may differ from the clinically significant cardiac amyloidosis occassionally seen in younger patients.

Fine-needle aspiration biopsy of spleen in diagnosis of generalized amyloidosis

Fine-needle aspiration biopsy of the spleen was performed on 18 patients shown to have amyloid deposits in other organs and on 17 control patients being investigated for proteinuria. Of the 18 patients with amyloid disease smears of splenic aspirate were positive in all cases, renal biopsy was positive in 16 out of 16 cases, and rectal biopsy was positive in seven out of 11 cases. None of the splenic smears were positive in the 17 control patients and no amyloid was found in the kidney in 15 of these patients on whom renal biopsy was performed. Splenic aspirate biopsy seems to be a simple and safe procedure for the diagnosis of amyloidosis. It is as accurate as renal biopsy and more accurate than rectal biopsy.

Clinicopathological conference: A case of unsuspected chronic inflammatory disease

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