Uncommon Case of Light Chain Primary Amyloidosis with Negative Bence Jones Protein and Positive Congo Red Stain in A 31 Years Old Sudanese Patient

Mujahed Nooraldaem Mirghani Adam; ismail Osman Khalid; ali Seedahmed Mohamed Ali; alkhair Abd Almahmoud Idris

doi:10.5455/CRSM.20241124010509

Abstract
A 31 years old male non diabetic or hypertensive, medically free who had unremarkable part of mild hepatosplenomegally, loss of weight and immunoglobulin light chain (AL) Amyloidosis. This patient underwent Trephine biopsy and Bone Marrow aspiration to confirm the diagnosis. Light microscopy showed deposition of Amyloid, focal areas with excess infiltration by plasma cells, cytoplasmic and background infiltration by eosinophilic materials is noted in Trephine biopsy without fibrosis. slightly blood diluted bone marrow aspirate with scattered granulocytes and plasma cells. Touch imprint showed hypercellular bone marrow with excess infiltration by plasma cells around 34% abnormal form and marked interstitial deposition of hyaline material Amyloids are noted. Overactive granulopoiesis with ordered maturation, increased eosinophils. Bence Jones protein was negative in the urine. We finally diagnosed this patient as having primary AL Amyloidosis by Congo red staining under polarizing microscope and started the treatment.

Key words: Light Chain, Primary Amyloidosis, Bence Jones Protein, Sudan