Diagnosis and therapy of chronic systemic co-infections in Lyme disease and other tick-borne infectious diseases

Townsend Letter for Doctors and Patients, April, 2007 by Garth L. Nicolson

Other tests that are offered for LD have been criticized. For example, diagnosis of LD based on culture of B. burgdorferi is completely unreliable. (7) One laboratory offers a one-step Lyme antigen urine test (LUAT), but some researchers have criticized this test for its high rate of false-positive tests. (8) Similarly, some IFA tests are suspect because they are almost universally positive. Most consider a patient positive if Bb antigens (EIA plus Western Blot analysis) are present in blood serum in more than one test, or the patient is PCR-positive for Bb.

Diagnosis of Tick-Borne Co-Infections: Mycoplasma, Babesia, Ehrlichia, and Others

Co-infections complicate the diagnosis and signs/symptoms of LD. These infections can also occur in various combinations. For example, another tick-borne infection is caused by the intracellular protozoan Babesia spp., first described in domestic animals in Romania. (9) There are over 100 species of the genus Babesia, but most infections in humans in North America are caused by Babesia microti and in Europe by Babesia divergens and Babesia bovis. About 20-40% of cases of LD show Babesia co-infections. When both infections are present, the number of signs/symptoms, their severity, and the duration of illness can be greater in the early stages of disease, (9) including high fever, chills, generalized weakness, gastrointestinal symptoms (anorexia, nausea, abdominal pain, vomiting, diarrhea, among others), anemia, muscle and joint pain, respiratory problems, and dark urine. This combination of infections can be lethal in some patients (about seven percent of patients can have disseminated intravascular coagulation, acute respiratory distress syndrome, and heart failure), but the majority of patients with Babesia spp. have the chronic form of the infection. In Babesia infections, patients can show mild-to-severe hemolytic anemia (probably correlating with the protozoan colonization of erythrocytes, which can be seen by experienced individuals in blood smears) and a normal to slightly depressed leukocyte count. (9) However, this is usually not seen in patients who have progressed to the chronic phase of the disease.

We and others (10) have found that the most common co-infection with Bb are various species of Mycoplasma. Approximately 60-75% of LD patients also have mycoplasmal co-infections (Mycoplasma fermentans > Mycoplasma hominis > Mycoplasma pneumoniae, M. genitalium, M. penetrans, other species). In some cases, multiple mycoplasmal infections are present in LD patients. The presence of mycoplasmal infections complicates the diagnosis and treatment of LD, and some of the generalized signs/symptoms found in Borrelia-positive patients are also found in Mycoplasma-positive patients. (5,6)

Like the Bb spirochete, mycoplasmas are found at intracellular locations in various tissues and are only rarely found free in the blood. This can make detection difficult, and, in some patients, the appearance of Bb and various mycoplasmas in their white blood cells can be cyclic. We recommend testing for mycoplasmal infections in LD, using the most sensitive PCR procedures to detect DNA in white blood cells. (5,6,11) In addition to LD, mycoplasmal infections have been found at high incidence (40-60%) in CFS, Fibromyalgia syndrome, rheumatoid arthritis, Gulf War Illness, and neurodegenerative diseases. (5,6,11,12) These are emerging infections, and the medical community is just beginning to respect the involvement of this type of co-infection in many clinical conditions.