Anemia

Anemia is defined as having a low red blood cell count that is found in a blood test known as a Complete Blood Count (CBC). It commonly causes fatigue; but it can also be associated with a variety of other symptoms such as shortness of breath and angina. It has many causes, but it can be categorized as falling into one of three categories: bleeding, destruction of red cells by an immune cause, or low production of red blood cells in the bone marrow (the blood making factory of the body).

Tests looking at iron counts and iron stores in the body are useful in differentiation of these potential causes. Bleeding from a gastrointestinal or uterine source, or by trauma is usually associated with a low blood iron and low iron stores. Low bone marrow function can be associated with decreased production of the other blood elements, the white blood cells and platelets. Peripheral destruction of red cells can be deduced by looking at blood tests that show elevated serum free hemoglobin and low haptoglobin levels.

The history and the physical exam assists in diagnosing the type of anemia that a patient has. In a menstruating woman, asking about the frequency, length and volume of menstruation often leads to the correct diagnosis. Gastrointestinal bleeding can be seen as frank blood emerging from the anus, to maroon colored stools. Peripheral destruction is invariably immune in origin, and is associated with other symptoms and signs of autoimmunity, such as rashes, swelling and fever.

I saw a 41 year old woman patient at the Arlington Free Clinic who presented with fatigue, sleep disturbance, and irregular menses. Her CBC showed a mild anemia, with normal blood iron counts. Further discussion with the patient revealed that the patient was having a lower volume of menses and night sweats. Her blood Follicle Stimulating Hormone (FSH) (stimulated in the hypothalamus by low estrogen in the ovaries) levels were not in the menopausal range. She then mentioned that she had an episode of Dengue fever many years ago in Venezuela, which was associated with anemia.

Dengue is a mosquito borne viral infection that is commonly seen in the Caribbean. It can cause peripheral destruction of red blood cells in what is called hemolytic anemia. But it can also cause a suppression of red blood cell production in the bone marrow.

This patient may have a chronic mild anemia as a rare sequela of Dengue fever, which is not causing her symptoms. This would have to be confirmed with a bone marrow biopsy, which in her case would only be of academic interest. She most likely has symptoms consistent with peri-menopause. Hormone therapy in the form of birth control pills is a good treatment to treat the symptoms of peri-menopause. Because she has a history of a benign breast tumor, and a very strong family history of breast cancer, I decided to place her on a non hormonal treatment that can also alleviate her symptoms instead. Duloxetine, a selective serotonin and norepinephrine uptake inhibitor (SSNRI) has been shown to be helpful in her condition, and I placed her on it.

In this case, the anemia was a red herring. Dengue fever is a nasty disease, and can have long term consequences. The anemia is thankfully mild, and asymptomatic.

It does give one second thoughts, however. about taking a Caribbean vacation.