Norihiro Suga

Differential diagnosis of localized and systemic amyloidosis based on coagulation and fibrinolysis parameters

Background: A simple assay that can discriminate between localized and systemic amyloidosis is needed. Methods: Coagulation and fibrinolysis parameters were measured in subjects with active or progressive systemic amyloidosis (Group A; 9 patients), systemic amyloidosis in complete remission (Group B; 6 patients), localized AL amyloidosis (Group C; 6 patients), monoclonal gammopathy of undetermined significance (Group D; 5 patients), chronic glomerulonephritis with proteinuria (Group E; 22 patients), or glomerulonephritis in complete remission (Group F; 11 patients). Results: No significant differences were noted between Group A and the other groups in the international normalized ratio of prothrombin time, activated partial thromboplastin time, and levels of antithrombin and plasminogen. Levels of thrombin–antithrombin (TAT) complexes, fibrinogen, fibrinogen degradation product d-dimers, and plasmin-α2–plasmin inhibitor complexes (PIC) were significantly elevated in Group A. All patients that showed TAT complexes, fibrinogen, and PIC levels greater than 4.2 ng/mL, 399 mg/dL, and 1.4 μg/mL, respectively, had active or progressive systemic amyloidosis. All patients with TAT complex levels less than 3.6 ng/mL, fibrinogen levels less than 355 mg/dL, and PIC levels less than 0.9 μg/mL had localized AL amyloidosis. Conclusion:Analyses of TAT complexes, fibrinogen, and PIC can be used to differentiate localized AL amyloidosis from systemic amyloidosis.

Membranous nephropathy (bubbling appearance and spike formation) without immunoglobulin deposition in a patient with systemic lupus erythematosus.

A 53-year-old Japanese man with systemic lupus erythematosus developed proteinuria and hematuria after a urinary stone episode. A light microscopic study of a kidney biopsy specimen demonstrated a bubbling appearance and spike formation of the basement membrane. Immunofluorescent studies revealed that there were no significant depositions of immunoglobulins, such as IgG (−), IgA (−), IgM (±), κ light chain (±), λ light chain (±), or C3 (−) in the glomerular capillary wall, though C1q was present as one-plus positive staining in mesangial areas. Electron microscopic studies showed that the thickness of the basement membrane varied from thin to thick without electron dense deposits, and that the cellular components of the podocyte were irregularly present in the basement membrane. Urinary protein decreased after the usage of prednisolone and mizoribine; however, proteinuria aggravated after an episode of urinary stone during the same treatment.

Systemic AA amyloidosis in a patient with lung metastasis from renal cell carcinoma

AA amyloidosis occurs in patients with high levels of serum amyloid A protein (SAA), which is produced by liver cells in response to signals from several pro-inflammatory cytokines. Chronic inflammatory disease is a major cause of AA amyloidosis; however, malignant neoplasms are rarely reported to be associated with AA amyloidosis. We report herein a case of a solitary lung metastasis of renal cell carcinoma associated with systemic AA amyloidosis. Pathological specimens of the resected lung tumor demonstrated renal cell carcinoma, and the presence of IL-1β, IL-6, and TNF-α in the lymphocytes and plasma cells surrounding the tumor cells, and AA amyloid in the vascular area, but not in metastatic clear cells. Four weeks after surgery, serum IL-6, SAA, and CRP levels normalized. Although this case is very rare, it is full of interesting suggestions about the pathogenesis of malignancy-related systemic amyloidosis.

A case of chronic kidney disease with thrombotic microangiopathy in a hematopoietic stem cell transplant recipient

A 23-year-old Japanese man who had undergone hematopoietic stem cell transplantation for acute lymphocytic leukemia from an HLA-identical sibling 6 years earlier developed proteinuria and impaired kidney function. Kidney biopsy revealed thrombotic microangiopathy with a moderate increase in mesangial matrices and glomerular microaneurysm featuring retention of red blood cells. The patient’s kidney function gradually deteriorated, requiring the institution of treatment with angiotensin II receptor blockers and angiotensin-converting enzyme inhibitors, and progressing to continuous ambulatory peritoneal dialysis 4 years after the initial kidney biopsy. Eventually, kidney transplantation was performed with his mother as the donor. His kidney function is stable on immunosuppressive drugs at 2 years after transplantation. This report reflects the growing number of patients with chronic kidney disease with thrombotic microangiopathy all over the world.

Effects of combination therapy with angiotensin II type I receptor blockers and calcium channel blockers on renal function in hypertensive patients: A retrospective, real-world comparative study

BACKGROUND Combination therapies with angiotensin II type I receptor blockers (ARBs) and calcium channel blockers (CCBs) are frequently administered to hypertensive patients, because these regimens have renoprotective and antihypertensive effects. However, few studies have focused on the renoprotective effects of individual CCBs when combined with ARBs for hypertension. METHODS Two hundred eighty-six outpatients prescribed three different CCBs (benidipine [CAS 91599-74-5], amlodipine [CAS 111470-99-6] and controlled release nifedipine (nifedipine CR) [CAS 21829-25-4]) for hypertension in combination with ARBs during a 4-year period were registered in a retrospective comparative study. The factors that influenced the appearance of renal events defined as doubling of serum creatinine were investigated. RESULTS The renal event rate was significantly lower in the benidipine than in the amlodipine (p < 0.05) and nifedipine CR (p < 0.01) groups. Multivariate analysis revealed hazard ratios for renal events to be significantly higher with chronic kidney disease (CKD) and lower with benidipine. Moreover, among patients with CKD, the benidipine group showed a significantly lower renal event rate than the amlodipine (p < 0.05) and nifedipine groups (p < 0.05). CONCLUSION In hypertensive patients treated with ARB and CCB, benidipine exhibits a better renoprotective effect than other drugs of this class (amlodipine and nifedipine CR).

Morganella morganii Peritonitis Associated with Continuous Ambulatory Peritoneal Dialysis (CAPD) after Colonoscopy

A 79-year-old man on continuous ambulatory peritoneal dialysis (CAPD) developed abdominal pain and cloudy peritoneal fluid two days after colonoscopy that revealed multiple diverticula. The white blood cell count was 9,000 cells/μL, C-reactive protein level was 6.86 mg/dL, and the white blood cell count of the peritoneal fluid was 7,800 cells/μL, suggesting acute peritonitis. Empiric therapy consisting of cefazolin and ceftazidime slowly improved the patients symptoms. The initial microbiological examination of the peritoneal fluid demonstrated Morganella morganii. He was changed from CAPD to hemodialysis. It is important to consider M. morganii peritonitis in patients with colonic diverticula.

Hypertensive Crisis and Left Ventricular Thrombi after an Upper Respiratory Infection during the Long-term Use of Oral Contraceptives

A 34-year-old woman who had been using oral contraceptives for 10 years developed hypertensive crisis with papilloedema after an upper respiratory infection. Laboratory data showed hyperreninemic hyperaldosteronism and elevated levels of fibrinogen, fibrin, and fibrinogen degradation products. Echocardiography demonstrated two masses (18 mm) in the left ventricle. On the fourth hospital day, cerebral infarction, renal infarction, and upper mesenteric artery occlusion suddenly occurred despite the blood pressure being well-controlled using anti-hypertensive drugs. Echocardiography revealed the disappearance of the left ventricular masses, which suggested left ventricular thrombi. Cessation of the contraceptives and administration of heparin, warfarin, and anti-platelets drugs improved her general condition.

Fat Embolism Syndrome: An Autopsy-Proven Case Involving a Patient on Dialysis and Systemic Scleroderma:

A 66-year-old woman receiving continuous ambulatory peritoneal dialysis developed acute respiratory distress 12 hours after a fall. Blood gas analysis revealed hypoxia (PaO2 67.7 torr) and metabolic acidosis with an increased anion gap, consistent with lactic acidosis (lactate, 86.5 mg/dL; normal range, 4.0–16.0). Magnetic resonance imaging showed a lumbar vertebral body fracture. On the fourth hospital day, the patient died of multiorgan failure and disseminated intravascular coagulation. Postmortem studies revealed fat emboli in the systemic circulation, ie, fat embolism syndrome. Diagnosing fat embolism syndrome can be difficult in patients on dialysis or in those with collagen vascular or pulmonary diseases.