Primary Systemic Amyloidosis with Extensive Gastrointestinal Involvement
A 42-year-old African American woman, born and raised in the United States, presented to the hospital with diarrhea, nausea and intractable vomiting with inability to tolerate oral feeding for 1 week. The patient had multiple prior visits to another institution with similar complaints, where a provisional diagnosis of gastroesophageal reflux disease was made from esophagogastroduodenoscopy. Upon further enquiry, she reported these symptoms to have started more than a year prior to the index presentation. Physical examination at the time of admission revealed a cachectic and disoriented young woman. Other pertinent positive findings of physical examination included hepatomegaly (20 cm) with ascites and bilateral pitting type of pedal edema.\nAn initial set of laboratory studies showed microcytic, hypochromic anemia (hemoglobin 8.4 g/dl), abnormal coagulation parameters (PT 17.1 s, aPTT 37.1 s), renal dysfunction (BUN 37 mg/dl, serum creatinine 2.0 mg/dl), abnormal liver enzymes (alanine transaminase 51 IU/l, aspartate transaminase 77 IU/l, markedly elevated alkaline phosphatase of 1,655 IU/l with normal bilirubin levels), profound serum hypoalbuminemia (1.5 gm/dl) and nephrotic range of proteinuria (urine dipstick protein assay showed 5+ proteinuria and the spot urine protein/creatinine ratio was 5.7). Additional work-up done for evaluation of abnormal liver enzymes including viral hepatitis panels (hepatitis A, B and C), ANA, anti-smooth muscle antibody, anti-liver kidney microsomal antibodies and anti-mitochondrial antibody was negative. Serum immunofixation revealed IgG lambda monoclonal protein. Urine immunofixation was negative. An echocardiogram revealed concentric left ventricular hypertrophy with a normal ejection fraction of 78%. A computed tomography scan of the abdomen showed pelvic ascites with mild, diffuse bowel wall thickening.\nThe patient's hospital course was marked by the persistence of diarrhea with minimal response to presumptive therapy with antibiotics (intravenous metronidazole and oral vancomycin). Stool work-up done for diarrhea revealed no infectious etiology. The patient had deteriorating renal function necessitating renal replacement therapy. She had a self-limited episode of hematemesis.\nThe patient underwent esophagogastroduodenoscopy and colonoscopy that revealed no gross mucosal lesions. Multiple random biopsies were taken from the stomach, duodenum, terminal ileum, colon and rectum. Biopsy results showed eosinophilic, acellular, globular deposits in the lamina propria and submucosa which stained positively with Congo, consistent with amyloidosis (fig. ). A subsequent bone marrow biopsy revealed normocellular bone marrow with trilineage maturation and diffuse extracellular eosinophilic, amorphous material consistent with amyloidosis (fig. ). A definitive diagnosis of primary systemic light-chain amyloidosis with gastrointestinal tract involvement was made. The patient was not considered for autologous stem cell transplantation, since the outcomes of autologous stem cell transplant in patients with multisystem involvement are often poor and fraught with a high mortality risk. She was subsequently referred to another institution for further management.