A 50-year-old man comes with a history of abdominal pain, weakness, lightheadedness, palpitations and shoness of breath. On examination, glossitis along with hyperpigmentation of skin of dorsum of hands and feet and abnormal pigmentation of hair was observed. The family of the patient told that they have observed frequent episodes of increased irritability from the past 1 year. Given below are the laboratory findings and the peripheral blood smear. Later bone marrow aspiration was also done. Hb: 9gm% MCV: 110fl MCH: 36Pg MCHC: 34gm/dl Reticulocyte count: 0.1 x 10^9/L LDH: 600 U/L Indirect bilirubin: 1 mg/dL S. iron: Normal S. Ferritin: Normal WBC: 2 x 10^9/L Platelet count: 90 x 10^9/L PERIPHERAL BLOOD SMEAR BONE MARROW ASPIRATION What is the in infective form of the organism causing the above condition: -
High-Yield Explanation
This is a case of megaloblastic anemia due to Diphyllobothrium latum infection. Lab findings show increased mcv, LDH, indirect bilirubin and normal iron studies, and low reticulocyte, WBC and platelet count. Pbs shows hypersegmented neutrophil. Bone marrow aspiration study shows megaloblasts. DIPHYLLOBOTHRIUM LATUM Humans acquire the infection by ingesting infected raw or smoked fish with plerocercoid larva which is the infective form. Within 3-5 weeks, the tapeworm matures into an adult in the human intestine. Because the tapeworm absorbs large quantities of vitamin B12 and interferes with ileal B12 absorption, vitamin B12 deficiency can develop. Praziquantel (5-10 mg/kg once) is highly effective. Parenteral vitamin B12 should be given if B12 deficiency is manifest.