In article <Pine.3.89.9506291107.A16665-0100000 at kb.usm.my>,
dharan at KB.USM.MY (InduDharan Manon) wrote:
>To Whomsoever it may concern,
>This is to bring your attention to a recent problem which we encountered
>in the city of Kota Bharu in Malaysia. We in the Department of ENT of the
>University Sains Malaysia were faced with an unusual foreign body of the
>ear in some of our patients. Few of them presented with complaints of an
>insect in the ear, while others presented with various comlaints like
>pain, bleeding and vertigo. On examination we found a red haemorrhagic
>bulla which on removal was found to be the blood filled bloated body of a
>tropical cattle tick which was identified as Boopilus microplus. Removal
>of this tick immediately relieved the complaints, though the ear drum is
>partially damaged in most of the cases. One of the most recent cases
>presented with a history of insect in the right ear and sudden onset of
>right lower motor neuron paralysis of the seventh cranial nerve(facial
>palsy) of three days duration. On examination the finding was a "typical
>haemorrhagic bulla". Due to the history of the insect, we tried removal
>and it was found to be the cattle tick mentioned above. The ear drum was
>torn at the site of attachment of the tick, but the middle ear as could be
>seen through the tear was clean and dry. Surprisingly within 48 hours the
>facial palsy recovered! Is there anybody who know of any neurotoxins or
>enzymes in ticks that can produce neurological manifestations like this in
>animals or man? Is it possible to analyse this tick for any toxin that
>produced facial palsy? I would much appreciate a reply. Thank you,
>Dr.R.Indudharan,
>Lecturer, Department of Otorhinolaryngology,
>PPSP, University Sains Malaysia,
>16150 Kubang Kerian, Kelantan, MALAYSIA
> Fax. 09-7653370
> E-mail. dharan at kb.usm.my
While some ticks certainly do produce neurotoxins, Boophilus sp, as far as I
know, are not usually considered to do so. In any case, the symptoms are
usually a generalised ascending flaccid paralysis rather than a localised
problem.
I wonder, given the proximity of the facial nerve to the point of attachment,
if local inflammation and swelling might account for the observed palsy?
Just a thought,
James Watson
Veterinary Clinical Pathologist.
