Iron Deficient Anemia??

by Allan Platt, PA-C, MMSc, DFAAPA

John is a 40 year old male who was referred to GI medicine for colonoscopy by his primary care provider because of persistent microcytic anemia that did not correct with iron supplementation. The PCP was worried about occult GI bleeding  from a colon cancer despite a negative FOB test.

The following is John’s lab slip at his PCP visit.

Taking a further history, John has been slightly anemic all his life, as well has his older brother and his father. They had always been counseled to supplement with iron and eat iron rich foods because the small size of the red blood cells.

The lab report details a high retic microcytic anemia with elevated indirect bilirubin and LDH. The peripheral smear is showing microcytes and target (bulls-eye) cells.

The high retic count should make the clinician consider acute bleeding or hemolysis. The high indirect bilirubin and LDH confirms hemolysis. Microcytosis should bring up four differential diagnosis remembered by the mnemonic TICS.

T – Thalessemia

I – Iron deficiency

C- Chronic Inflammation Elevated hepcidin and inflammatory block

S- Sideroblastic which is caused by lead toxicity or hereditary

The proper work up includes Iron studies for iron deficiency: Ferritin, Serum iron, TIBC. A hemoglobin electrophoresis for diagnosing thalassemia, a erythrocyte sedimentation rate (ESR) or c-reactive protein for inflammation, and a lead level to rule out toxicity.

John had further tests revealing normal iron stores, no lead, and a normal ESR. His hemoglobin electrophoresis revealed three normal hemoglobin types with an abnormal percentage pattern

HbA 1: 94% – slight decrease

HbA 2: 5%  – slight elevation

HbF:    1%

This is all consistent with John having thalassemia, the most common genetic cause of anemia world wide. More specifically John has beta thalassemia minor (trait) which causes a mild asymptomatic lifelong microcytic anemia with or without hemolysis. John’s whole family should be tested and given genetic counseling. Iron supplements should not be used unless iron deficiency is diagnosed with a low ferritin value.

References:

https://www.nhlbi.nih.gov/health/health-topics/topics/thalassemia

https://emedicine.medscape.com/article/206490-overview

 

See Allan Platt, PA-C, MMSc, DFAAPA speak this summer at the GAPA 2018 Summer Conference in Sandestin, FL. Click here for details.

Share this story:

Share on Facebook Share on Twitter Share on LinkedIn Email to a Friend
GAPA