Histologic effect of doxycycline sclerotherapy on rat femoral nerve.
BACKGROUND
This study stems from an encounter with a phrenic nerve paralysis in a patient following doxycycline sclerotherapy for treatment of chylous fistula. The purpose of this study is to identify possible histologic evidence of doxycycline-induced nerve injury.


METHODS
The femoral nerves of CD rats were used as the in vivo animal model. The nerves were exposed to varying concentrations doxycycline and normal saline was the control. The nerves were studied at several time intervals using two different staining techniques.


RESULTS
The results suggest that topical doxycycline induces tissue reactions which are different from normal saline. These reactions include stimulation of a local giant cell inflammatory reaction and disruption of the myelin sheath.


CONCLUSIONS
Despite the fact that this study does not give physiologic evidence of neurotoxicity, the histologic results suggest that topical doxycycline may cause nerve damage directly or indirectly. We conclude that doxycycline should not be used for sclerotherapy where unprotected nerves are exposed to the agent until further physiologic tests are performed to prove its safety.
Department of Otolaryngology-Head and Neck Surgery, University of Arkansas for Medical Sciences Little Rock, USA.
D J
DJ
Kirse
J Y
JY
Suen
S J
SJ
Stern
R F
RF
Schaefer
P K
PK
Roberson
D000287:Administration, Topical; D000818:Animals; D002913:Chyle; D003711:Demyelinating Diseases / Q000139:chemically induced* / Q000473:pathology; D004318:Doxycycline / Q000008:administration & dosage / Q000494:pharmacology*; D005267:Femoral Nerve / Q000187:drug effects* / Q000473:pathology; D005402:Fistula / Q000628:therapy; D006801:Humans; D010243:Paralysis / Q000209:etiology; D010791:Phrenic Nerve; D051381:Rats; D012597:Sclerosing Solutions / Q000008:administration & dosage / Q000494:pharmacology*; D015911:Sclerotherapy / Q000009:adverse effects*
D012597:Sclerosing Solutions; D004318:Doxycycline