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It’s 2 am and I am up with a migraine but at least I have figured out why. Ten years ago, I was diagnosed with iron deficiency anemia due to malabsorption syndrome. I was pretty sick by the time I sought help because the onset of the anemia was insidious (5+ years) and I was distracted by my husband’s illness. Intravenous iron infusions fixed me right up, and now the biggest related problem I have is the insurance co-pay for the infusions. In other words, I am completely fine as long as I get iron infusions.

Experiencing Pica

All doctors should be patients occasionally so that they understand what it’s like to sit in a doctor’s waiting room and to learn things about physiology you can’t get from books. I first experienced iron deficiency 30 years ago when I was pregnant. The wound center was under construction and the hospital temporarily gave me the office of the hospital Food Services Director. This saved my life as a pregnant woman. They forgot that my office key also unlocked the cafeteria in which there was the world’s best crushed ice machine. Normally I don’t even put ice in my iced tea, but when I was pregnant, eating crushed ice was an uncontrollable compulsion. The precise medical term for compulsive ice-eating is “pagophagia” but the medical condition is called “pica,” a word derived (apparently) from the Latin word for magpie, a bird known for its strange eating habits. An online medical dictionary describes pica as “a craving for something that is not normally regarded as nutritive, such as dirt, clay, paper, or chalk…” However, the word “craving” does not capture the level of compulsion involved with pica. Thankfully, my personal experience with pica made me a more sympathetic physician when an anxious nurse entered my office and locked the door in order to privately confess an uncontrollable desire to eat the grout in her new tile floor. Ashamed and frightened, she wanted to know if she needed urgent psychiatric treatment. I was able to reassure her that all she needed was iron – and treatment for her heavy menstrual bleeding.

Physician, Heal Thyself

Unfortunately, 20 years after experiencing pagophagia while pregnant, I was not able to diagnose pica in myself when I developed “tomatophagia.” Yes, that is a real thing, described in a 1999 New England Journal letter to the editor. Pica occurs in up to 58% of patients with iron deficiency anemia, of which pagophagia accounts for 88%. However, tomatophagia is a real and equally inexplicable manifestation since none of the food substances one feels compelled to eat actually contain much iron. In addition to tomatophagia, I also developed a compulsion to eat wintergreen mints – a condition which does not have a Latin name. When I say compulsion, I mean that I ate at least 5 boxes of cherry tomatoes a day and at least two entire bags of wintergreen mints. The mints are individually wrapped, to the great frustration of someone with pica. I would get up in the middle of the night to go buy cherry tomatoes or wintergreen mints. I also needed at least one large cup a day of a particular crushed ice drink from a fast-food place. When my problem was finally diagnosed, my hemoglobin was only 7.4 gm/dl (normal is 12.0 – 16.0 gm/dL) and my ferritin was only 2 ng/mL (normal is 13 – 150 ng/mL). I had also driven my family crazy by constantly crunching ice and breath mints and demanding that someone run to the grocery store every day for cherry tomatoes. After a series of intravenous iron infusions, I found myself unable to even look at tomatoes or wintergreen mints and had no desire to chew ice. (I was also no longer breathless just getting up from a chair.)

It might be the Ferritin, stupid

Low iron levels eventually cause anemia because the body needs iron to make red blood cells, but anemia happens rather late in the process of iron deficiency. First the body uses all available stores of iron. And that’s where the story gets interesting. The medical literature associates pica with iron deficiency anemia, as if the trigger for the strange food cravings was the anemia rather than the lack of iron. I can tell you that at least that particular form of pica is not due to the anemia per se but begins long before the anemia. I had a complete blood count three months ago for an unrelated reason and knew I was not anemic. However, at about the same time, I started having severe migraines again. At first the headaches happened only occasionally but then they became a daily problem and even began to wake me from sleep. In retrospect, about 4 months ago I gradually started writing fewer editorials and blog posts and taking longer to answer emails. I can’t explain why, except that thinking required more effort. I wasn’t forgetful, but it was harder to get my thoughts on paper. Then, 3 weeks ago, I started driving out of my way every day to get a mango freeze from Taco Bell. My excuse was that it is very hot outside, but I had to look for a Taco Bell on my GPS if I was running an errand out of my neighborhood because I needed one NOW. Last week my son came home from several months away at military training and watched me eat a very large box of cherry tomatoes while standing in the kitchen. He said with raised eyebrows, “Mom, you are doing it again.”

Doing what? It creeps up on you, pica does. I just hadn’t noticed it. My hemoglobin is “low normal” (although it is a gram lower than it was two months ago). My serum iron is normal at 138 mcg/dL and my ferritin is 30 which is also a “normal” level, per the lab, but it’s 75% less than it was after my last infusion. I can only deduce that it’s the drop in ferritin that has caused me to have pica again. My quick perusal of the internet has found a lot of papers linking migraines to iron deficiency and “brain fog.” I think the recent, frequent migraines are due to the same problem – based on the time course.

Is this relevant to wound patients?

This whole thing has gotten me thinking about patients with chronic wounds. Five years ago, I revolutionized my own wound care practice by working on only two simple nutritional things: 1) making sure patients had a Vitamin D-25 of at least 30, and 2) making every patient with a non-healing wound take L-arginine. I’ve also been checking thyroid panels because that’s another problem that’s easy to fix and common in heart failure patients who represent nearly a quarter of my patients. Those interventions may not seem like much, but depressed patients started to laugh, weak patients started to get out of their recliners, cardiac ejection fractions have improved in heart failure patients and wounds that were not making progress have healed. It’s a lot of benefit for a small amount of effort on my part, but at least I more or less understand the physiology of those interventions.

Nearly all of our patients are anemic – many for unfixable reasons like renal failure, but often diagnosed as “anemia of chronic disease.” Like their other doctors, I have shrugged my shoulders over yet another hopeless problem that is not officially “my job.” These patients often also have reduced mental functioning for reasons too long to even list (age, vascular disease, medications, poor sleeping, etc.). But since I’ve been taking dietary histories of patients with wounds in order to get them to eat better, I’ve noted that some will admit to strange food “preferences.” It occurs to me that maybe we are missing iron deficiency in our patients, and possibly many other people since pica is an embarrassing problem to own up to.

Ironically, I once found a serum ferritin of 2,000 in a patient with orange skin, spoon nails and non-healing wounds. That case, and my own puzzling situation are reminders of why just checking labs for iron deficiency is not going to work very well. Iron metabolism is so incredibly complex that it’s a superb argument against macro evolutionary theory. Human iron metabolism involves so many different organ systems that it has to be the creation of a God with a sense of humor. I have pica with serum ferritin and iron levels that would not normally cause concern. Based on past experience, it will be 3 months before the lab values will be bad enough for a doctor to be worried – by which time I will feel far worse than I do now. Clearly there’s a lot about iron metabolism and pica we don’t understand.

I am relieved to know my current “issues” are my old friend, iron deficiency, that is easily gotten rid of. I am scheduled for an iron infusion, and, Oh joy! there’s a Taco Bell on the way so I can get one last mango freeze. However, I do wonder whether there’s a lesson in here for my patients and if so, what it is?