Support Group

[November] Articles of Interest

Posted on 12/13/2012. Filed under: PubMed, Support Group | Tags: , , , , , , , , , , , , , , , , , |

Dr. Wright discussed the following articles with the members of the Borrelia (Tick-borne Relapsing Fever and Lyme disease) patient support group in their November meeting:

1. Autoimmunoreactive IgGs from patients with postural orthostatic tachycardia syndrome. (link to abstract)
Cardiologists at the Mayo Clinic in the Department of Internal Medicine looked at people with postural orthostatic tachycardia syndrome (POTS) to see whether they had autoimmune antibodies. The study revealed 40 unique proteins, many of which are associated with cardiac problems. The study concluded that patients with POTS do have autoantibodies, and these autoantibodies cross-react with cardiac proteins, possibly causing changes in cardiac function.

Dr. Wright commented that many patients with tick-borne illnesses have postural tachycardia, so in the case of damage to the cardiac muscle, it is unclear whether damage is caused by the infection or by the autoimmune issues associated with POTS.

2. Investigation of Borrelia burgdorferi genotypes in Australia obtained from erythema migrans tissue (link to full text)
A dermatologist in Australia conducted a study on four patients with erythema chronicum migrans (EM) (the bull’s-eye rash) to see which species of Borrelia patients were infected. PCR of central tissue biopsy revealed two strains similar to Borrelia burgdorferi (strain 64b), one isolate similar to Borrelia bissettii, and one similar to Borrelia valaisiana. Dr. Wright commented that it would be a good idea to do both a central lesion biopsy and a leading edge biopsy. This study suggests the presence of both Borrelia burgdorferi and Relapsing Fever Borrelia isolates in Australia.

3. A hard tick relapsing fever group spirochete in a Brazilian Rhipicephalus (Boophilus) microplus. (link to abstract)
One of Dr. Wright’s patients was planning a trip to Brazil, and he was reminded of this article from 2007, the first documented isolation of Borrelia from ticks in Brazil. The researchers found a species similar to the Relapsing Fever isolate Borrelia lonestari and labeled it Borrelia sp-BR. This species of Borrelia was found in the Rhipicephalus (Boophilus) microplus tick, a hard-bodied tick that feeds on cattle (it is also known as the southern cattle tick). This tick can be found in South and Central America, as well as in Africa, Asia, and Australia.

4. A novel relapsing fever Borrelia sp. infects the salivary glands of the molted hard tick, Amblyomma geoemydae. (link to abstract)
Japanese researchers have found a new, yet unnamed, species of Borrelia. It is phylogenetically related to B. miyamotoi and B. lonestari (both of which cause tick-borne relapsing fever). The new species was found in Amblyomma geoemydae ticks, which feed on cows and other large animals. Also found in 5% of the ticks studied was Borrelia sp. tAG, a species associated with reptiles.

5. Associations of passerine birds, rabbits, and ticks with Borrelia miyamotoi and Borrelia andersonii in Michigan, U.S.A. (link to full text)
A four-year study from Michigan, published in October 2012, examined ticks found on wild birds and rabbits to see what isolates of Borrelia they were carrying. Two strains of B. miyamotoi were found, and this was the first time B. miyamotoi was documented in ticks removed from wild birds. Most of the birds carrying ticks positive for B. miyamotoi were Northern Cardinals. Ticks found on birds and rabbits also tested positive for B. andersonii. The authors of the study conclude, “Given the current invasion of I. scapularis, a human biting species that serves as a bridge vector for Borrelia spirochetes, human exposure to B. miyamotoi and B. andersonii in this region may increase.”

Dr. Wright reminded patients that there are currently no commercially-available tests (in the U.S.) for B. miyamotoi and B. andersonii. He also recommended that people limit exposure to wild birds and bird feeders.

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[August] Articles of Interest

Posted on 08/26/2012. Filed under: PubMed, Support Group | Tags: , , , , , , , , , , , , , , |

Dr. Wright discussed the following articles with the members of the Borrelia (Tick-borne Relapsing Fever and Lyme disease) patient support group in their August meeting:

1. Humans Infected with Relapsing Fever Spirochete Borrelia miyamotoi, Russia (link) (PDF)

Dr. Wright drew attention to two figures from this article.

Figure 2

Examples of relapsing fever episodes in 2 patients with Borrelia miyamotoi infection.

Interesting Points:

  • This figure illustrates that an antibody test can be negative at anywhere between 15 and 37 days post-tick bite, even though a PCR may be positive. Each graph above represents episodes of relapsing fever in one patient from the study.
  • During the time that both patients were hospitalized with high-spiking fevers, antibody tests for Borrelia miyamotoi were negative.
  • Antibiotic therapy was not initiated until 30 days after the tick bite. If the patients had been infected with Rocky Mountain spotted fever instead of Borrelia miyamotoi, some would likely have died waiting to get treatment.
  • In cases where doctors are not sure which tick-borne infection a patient has–because symptoms of fever and myalgia come with many infections–it is important to start antibiotic treatment right away.
  • Dr. Wright reminded the group that, according to Israeli studies on Borrelia persica, prophylaxis does not work at 72 or 96 hours. If treating a patient with antibiotics later than 48 hours after a tick bite, doxycycline should be given for at least two weeks.

Figure 3 (Click image to enlarge)

Phylogenetic tree of Borrelia spp. detected in persons and ticks, based on flagellin gene fragment (A) and16S rRNA gene fragment (B).

Phylogenetic tree of Borrelia spp. detected in persons and ticks, based on flagellin gene fragment (A) and16S rRNA gene fragment (B). Sequences were aligned and analyzed by using MEGA4.1 software (www.megasoftware.net). Genetic trees were constructed from the partial nucleotide sequences of the flagellin gene and the 16S rRNA gene by using the Kimura 2-parameter model and the unweighted pair group method with arithmetic mean. Arrow indicates the 16 Borrelia spp. from Yekaterinburg in 2009 that had the same nucleotide sequence. Circles indicate sequences that we listed in GenBank (accession nos. GU797331–GU797346 and JF951378–JF951392). Sequences for B. burgdorferi sensu lato and relapsing fever borreliae are shown for comparison. Scale bars indicate genetic distance.

Interesting Points:

  • There appear to be three main types of Borrelia miyamotoi: 1) Russian/Asian, 2) European, and 3) U.S. and Japanese.
  • It’s possible that we have an undiagnosed Borrelia miyamotoi epidemic. It’s already been detected in wild turkeys in the U.S. If we had commercially-available tests for it, we’d likely be detecting it in people, too.
  • People who test positive for Borrelia hermsii with a low antibody titer could have Borrelia miyamotoi.
  • Researchers say that species like Borrelia hermsii that cause Tick-borne Relapsing Fever are only carried by soft-bodied ticks, but Borrelia miyamotoi is carried in two different U.S. species of hard-bodied ticks. If there is one exception, there are likely others.

2. Signs and significance of a tick-bite: psychiatric disorders associated with Lyme disease (link to abstract)

This is a study from the Netherlands in which a researcher reviewed the literature on psychiatric disorders and Lyme disease. The disorders most often associated with Lyme disease were:

  • depressive disorders
  • psychotic disorders
  • cognitive impairment
  • memory and concentration disorders

Dr. Wright mentioned a case of a child with “atypical psychosis” who turned out to have a Borrelia hermsii infection, and recommended that patients with psychiatric disorders of an unknown origin be screened for Borrelia infections.

3. Bell palsy in Lyme disease-endemic regions of Canada: a cautionary case of occult bilateral peripheral facial nerve palsy due to Lyme disease. (link to abstract)

  • About 25% of cases of Bell palsy in Canada are due to Lyme disease.
  • A facial palsy is a neurologic presentation of the infection, which means doctors missed the infection in its acute stage. For this reason, Dr. Wright believes it is more effective to treat patients with Bell palsy with IV ceftriaxone (as opposed to oral doxycycline).
  • In this study, researchers only looked for one isolate of Borrelia burgdorferi. It’s possible that if they had looked for multiple isolates, greater than 25% of Bell palsy cases would have been due to Borrelia infections.

4. Aseptic meningitis and adult respiratory distress syndrome caused by Borrelia persica. (link to abstract)

  • Borrelia persica is a relapsing fever species commonly found in the middle east and has been studied extensively by Israeli scientists.
  • In this study, they find that adult respiratory distress syndrome (ARDS) can be a complication of Borrelia persica infection.
  • ARDS is a known complication of Borrelia hermsii infection as well.
  • When a patient has ARDS, fluid accumulates in the lungs, and the patient has to be put on a ventilator. Dr. Wright suggests that perhaps we should be screening patients on ventilators for Borrelia infections.

5. Solitary erythema migrans in children: comparison of treatment with clarithromycin and amoxicillin. (link to abstract)

  • Clarithromycin and amoxicillin differ from ceftriaxone and doxycycline in that they cannot cross the blood-brain barrier. In advanced infections with neurological symptoms, it is important to be treated with an antibiotic that can cross this barrier.
  • To date, Dr. Wright knows of no study of prophylaxis in children; this would be helpful to have.

Disease prevention reminders:

Dr. Wright discourages patients from letting their pets sleep with them in their beds, as this is how many zoonotic infections can be spread. He also stresses the importance of keeping one’s house free of rodents (which carry ticks). “We still haven’t learned the Middle Ages lesson about rodents living with humans,” Dr. Wright said in reference to the bubonic plague.

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