Medical literature includes a great deal about yeast infections. Even more articles have appeared in the lay press, dealing not only with gynecologic infections, but gastrointestinal yeast and generalized yeast infestation of the body. Yeast is a hot topic, and as with most such topics, there are voices of measured reason, and other voices that attribute every possible health problem to yeast. Enthusiasm verging on zealotry (and paranoia) would recommend detoxifying every suspect case using special diets and other measures.
The final word on all of this is not yet in, and we certainly are not in a position to disparage research, whether coming from the perspective of medicine, nutrition, or any other discipline. But I would like to outline some aspects of yeast infection that we do understand, and how this problem may impact singers.
Yeast (referring to various types of Candida species) is a microbiologic organism that may be found in various parts of the human body. Under normal circumstances it may be a benign colonizer of moist surfaces, such the gastrointestinal tract. It is one of many microorganisms that share a common ecological niche, including a large variety of bacteria, and rarely, even some fungi (culturing the fungus Actinomyces from the tonsils is not unusual, for example).
The inner (mucous membrane) and outer (skin) surfaces of the body normally maintain a dynamic balance among the various populations of microorganisms. This balance is dictated by the usual parameters of competition in any ecological niche: availability of nutrients and physical conditions such as pH, temperature, and the presence or absence of other external factors that can encourage or discourage microbial reproduction. Yeast is a normal part of this flora. Furthermore, we ingest yeast daily, in the form of leavened foods (bread, beer) and as spores attached to the surface of fruit. Needless to say, in the presence of normally balanced and competitive microbial flora—whether in the mouth, GI tract, or other areas—small amounts of yeast are harmless and do not produce symptoms.
When the balance tips, however, yeast can gain the upper hand. Candida is not a particularly pathogenic organism, but it is opportunistic. When physical circumstances change, it is always ready to reproduce rapidly and take over an ecological niche that its former competitors have vacated. Even when this occurs, yeast is very rarely invasive, and usually only when systemic immunity is compromised, such as in patients who are immune suppressed (such as those with organ transplants, or HIV/AIDS).
Yeast infections are most commonly seen in the gynecologic area, but they can also occur in the head and neck, including the mouth, throat, pharynx, and larynx. When this happens, the patient may complain of a sore throat, hoarseness, or pain on swallowing. The classic appearance of white patches or a lace-like pattern covering the soft palate carries the name of “thrush” and is easy to diagnose. Milder cases where the white patches are not present are less obvious. Here, the mucous membranes of the vocal tract can be red, often with sticky, stringy mucus that is adherent. The symptoms are also less specific, and can mislead both the patient and the doctor.
What can cause such infections in an otherwise healthy individual? The most common causes are antibiotics and steroids, taken either as pills or as inhalers. Antibiotics work by attacking groups of disease-causing bacteria and reversing the course of a bacterial infection. They are, however, not specific enough, and also take out benign types of bacteria, the normal flora of body surfaces, as “collateral damage.” When these benign bacteria (which keep yeast under competitive check) are gone, yeast begins to reproduce. Eventually, an overgrowth of yeast and its associated symptoms develops.
Steroids in the vocal tract are usually taken as asthma inhalers. These may help control inflammation in the respiratory tract, but they also inhibit local immunity, and may allow for yeast overgrowth. Interestingly, clinical yeast infection in the nose is uncommon, despite the wide use of steroid nasal allergy sprays such as Flonase, Nasonex, Rhinocort, etc.
Doctors should suspect yeast in a singer who has been on multiple courses of antibiotics and steroids, and continues to have symptoms. These patients have often seen several different physicians, and with each visit received another course of another antibiotic. Another method of treatment, used by some physicians, involves giving a patient both antibiotics and steroids at the same time, whether orally or as a spray. The idea is to minimize the patient’s symptoms more quickly (steroids) while controlling the infection at the same time (with antibiotics). In some cases, however, the antibiotic may not be the best one for controlling the infection—the symptoms improve initially, due to the steroids, but the infection continues. The patient then goes on to a second or third antibiotic, or sees another doctor, and the background for yeast infection is created.
As mentioned above, the telltale white patches may not always be there, but the symptoms are low-grade sore throat, excess sticky mucus, and hoarseness. Not every patient with these symptoms has a yeast infection, but many do, and the diagnosis is missed. If you are prone to vaginal yeast infections, and especially if your symptoms fluctuate during your menstrual cycle, suspect yeast of the throat. A short course of antifungal medications (such as Diflucan) can lead to a dramatic improvement of sore throat or hoarseness in some cases.
How do you prevent such throat infections? If you need to be on a steroid inhaler, rinse your mouth after use. Also, this may be case for reducing high-sugar foods, and foods consisting of simple carbohydrates (these feed yeast), as well as foods and beverages that contain yeast. In cases of persistent throat, sinus, or chest infections, keep track of what antibiotics you have taken, especially if the course has been long (more than seven days), and consisted of several different antibiotics. And don’t be afraid to discuss this with your doctor, especially if your symptoms have not responded to antibiotics.
