Today I saw a patient who was worried about recurrent infections. I spend the whole year with infections and I have been told several times that my defenses are low – says the patient.
But what do we mean when we say that our defenses are low?
There are several contexts in which I see this term used. Some examples are: patients who have infections continuously, like the patient I saw today, requiring constant use of antibiotics. Women with recurrent candidiasis, with no resolution of the problem. Patients with recurrent herpes, one after another, even using antivirals. People with constant colds. Patients with persistent diarrhea. Thus, we can state that constant infections are a sign of low defenses.
Often, patients who have chronic fatigue also report that they have low defenses. Also patients who have inflammatory processes, joint pain, skin spots or oral ulcers (among other symptoms) believe they have low defenses.
Many people believe that with stress the defenses go down. When one loses a lot of weight, one also suspects that the defenses are lowered. It is also common to think that some medications such as antibiotics lower the defenses.
This popular wisdom is not without reason in many cases. However, in most of the patients I evaluate, there is no real quantification of defenses available, beyond a hemogram (basic blood count).
Quantification and treatments for low defenses
So, can defenses be measured? Yes, they can. The defense or immune system has many measurable components. And very important: some components of the defense system can be replaced. That is why it is very important to properly quantify the defenses with specialized blood tests, because if there is a low replaceable component this can mean the introduction of therapies that can change people’s lives. Thus, for example, immunoglobulins can be administered intravenously and also subcutaneously.
Some vitamins, although not strictly speaking defenses, are important in regulating the functions of the immune system. That is why it is also important to measure some vitamins that if they are low we can replace them, such as vitamin D.
On the other hand, when immunologists detect low defenses that cannot be replaced, we can use prophylactic vaccines. Thus, for example, persons with deficiency of some complement factors and who have recurrent infections may improve if anti-pneumococcal, anti-hemophilus and anti-meningitis vaccines are administered.
Persons with neutrophil deficiencies may benefit from the use of colony-stimulating factors; patients deficient in some cytokines may do so with some cytokines available for clinical use.
In other cases, even if quantification is normal, we can try to boost defenses, for example, by using bacterial or fungal vaccines that can be administered mucosally.
Many patients find benefit with some of these interventions.