Thalassemia Minor

[Guest cessna84]

I have a quick question regarding Thalassemia Minor. It's a gene that I've received from my family that shows wacky blood levels. I produce more blood cells than normal. It does not affect me at all, just shows up in my blood and I've always had it. I was recently picked up for a pilot slot and I am waiting to see when I go to Brooks for my flying class I. I'm no longer anemic, I've been taking folic acid to raise my hemaglobin/hematocrit levels and they are normal. Is this condition waiverable? I'll provide more details if needed, but I can't stress enough how it does not affect me at all.

Thanks.

[Guest JoeMama]

Quickly looking through AFI 48-123, Thalassemia is listed as disqualifying for flying duty. In one area, it specifies Thalassemia major specifically, and in a different section, no distinction is made.

Regardless, in the Aeromedical waiver guide, it looks like the flight docs don't see Thalassemia Minor as a big deal.

Just from reading through the guidelines, if you're disqualified for FC1 for Thalassemia Minor, my guess is a waiver would be pretty easy to get (especially with normal hemoglobin and hematocrit levels).

Let us know how it goes, so people in the future will have more info.

Good luck with the FC1!

[Guest doctidy]

You'll be fine as long as you are not anemic. Thal minor is not disqualifying, anemia is.

[Guest falcon84]

Hi,

I also have the thalassemia minor trait which does not effect me at all. I have documentation from a hematologist and a urologist and I was wondering if I should bring this documentation. Will I still get DQed for this? If I do, will it speed up the waiver process??

Thanks for your help.

-Scott

[Guest F16PilotMD]

CONDITION: THALLASSEMIA

I. Overview. Thallassemia denotes an inherited production abnormality of hemoglobin subunits. It is an autosomal recessive disease most commonly affecting people of Mediterranean or Asian origin (the heterozygous condition partially protects from malaria). The hemoglobin subunits involved include alpha, beta, delta, and gamma chains. Normal hemoglobin, Hgb A, is a tetramer composed of two alpha chains and two beta chains. Homozygous disease is not compatible with a long life. In “thallassemia major,” there is a defect in beta chain production. Here, a significant amount of hemoglobin is Hgb F (two alpha chains and two gamma chains). This tetramer is unstable, readily breaks down, and results in severe microcytic, hypochromic anemia. In contrast, “hemoglobin H disease” has a defect in alpha chain production. The resultant tetramer, Hgb H (four beta chains), is unstable producing severe microcytic, hypochromic anemia. Because Hgb H binds oxygen very tightly seldom do these individuals survive long life. Another more virulent alpha chain defect (four gamma chains---Hgb Bart’s) causes the deadly hydrops fetalis. Needless to say, it is heterozygous disease that is encountered in aircrew evaluations. In “thallassemia minor,” beta chain underproduction is countered with delta chain overproduction. Hemoglobin A2 (two alpha chains and two delta chains) is the result. This hemoglobin is also unstable; however, since it makes up only 3–7% of the RBC hemoglobin mass, rarely is there more than a mild anemia seen. Likewise, heterozygous alpha thallassemia (characterized by very small amounts of Hgb H and/or Hgb Bart’s) rarely produces more than a mild anemia.

II. Aeromedical Concerns. The homozygous thallassemias are incompatible with long life, let alone aircrew duties; however, the heterozygous thallassemias generally do not impair normal life and are compatible with aircrew duties. The only potential concern is a mild, microcytic, hypochromic anemia.

III. Information Required for Waiver Submission. Because iron deficiency anemia is a major cause for microcytic, hypochromic anemia, serum iron, TIBC (total iron binding capacity), and serum ferritin are required for initial waiver. In addition, hemoglobin electrophoresis is required for initial waiver.

Waiver Considerations. The asymptomatic aircrew member is a waiver candidate. Likewise, the aircrew member with minimal anemia is a waiver candidate. In fact, review of the Aeromedical Consult Service experience revealed 85 aircrew with thallassemia (all heterozygous). None of the twelve with mild anemia was disqualified. All told, almost 97% have received waivers. Waiver guidance for heterozygous thallassemias associated with other hemoglobinopathies can not be generalized and require individualized evaluation.

[Guest falcon84]

Thanks for the info. I have already consulted a urologist and a hematologist. Should I have these two doctors do a write-up stating that there is nothing wrong and should I bring that with me to Brooks just to speed up any waiver processes??

[Guest F16PilotMD]

I don't know if it will speed things up or not but I always recommend YES to your question.