Systemic Naloxone Infusion May Trigger Spasticity in Patients With Spinal Cord Injury: Case Series

Abstract

Background/Objective: Three patients with spinal cord injury (SCI) and 3 able-bodied (AB) patients were infused with naloxone during a study to examine their neuroendocrine function. An unanticipated side effect occurred during the naloxone infusion. All 3 patients with SCI, but none of the AB patients, experienced profoundly increased spasticity during the naloxone infusion. Our report describes this side effect, which has potential implications for the clinical treatment or scientific evaluation of individuals with SCI.

Methods: All patients were in good general health and medication free for 11 days or longer before the study. Each patient was placed on a 30-hour protocol to analyze pulsatile release of gonadotropins. Physiologic saline was intravenously infused on day 1 to serve as a control period for naloxone infusion on day 2.

Results: AB patients experienced no muscle spasm activity or any other side effects at any time during the study. In contrast, all 3 patients with SCI experienced a profoundly increased frequency and duration of spasticity in muscles innervated by the nerve roots caudal to their level of injury. In all 3 patients with SCI, spasticity increased only during the period of naloxone infusion. Within 1 hour of stopping naloxone, spasticity returned to baseline levels.

Conclusions: Naloxone infusion produced a differential effect on the muscle activity of men with SCI compared to AB men with intact spinal circuits. Consistent with previous studies, the results of this study indicate a relationship between opioid neuromodulation and spasticity after SCI.     

Herpes simplex virus infections and current methods for laboratory detection

Herpes simplex virus (HSV) is endemic in all societies throughout the world and produces year-round infections in all age groups. While orofacial and genital skin infections predominate, a significant minority of individuals develop more serious herpetic disease in the eye, meninges, and brain tissue. Perinatal infection of the newborn has a high likelihood of dissemination to multiple visceral organs, and immunocompromised patients can develop aggressive necrotizing skin lesions, as well as disseminated disease. HSV is not fastidious and is easily propagated in vitro; virus culture methods are straightforward and currently are offered in many community hospital microbiology laboratories. However, amplified nucleic acid probe assays have now been developed that are significantly more sensitive than culture, have fewer specimen collection and transport constraints, and can generate reliable results the same day of testing. Recent innovations in HSV antibody assays that use serotype 1- and serotype 2- specific reagents can now provide accurate serological separation of HSV-1 and HSV-2 infections by ELISA and Western blot (immunoblot) methods. Community hospitals should anticipate more frequent requests for these more sensitive and specific diagnostic tests. When reliable commercial assays become available, new serological and molecular tests may be within the scope of the community hospital laboratory.     

Antibiotics: effect on cryopreserved-thawed human sperm motility in vitro

Objective: To analyze the motility and fertilizing capacity of sperm treated with different antibiotics.

Design: Prospective comparative study.

Setting: Clinical and academic research environment.

Patient(s): Pooled cryopreserved donor sperm (n = 14).

Intervention(s): Sperm were washed with Percoll and resuspended in HEPES-buffered human tubal fluid medium containing either amoxicillin, of ioxacin, ciprofloxacin hydrochloride, nitrofurantoin monohydrate, doxycycline hyclate, cefuroxime axetil, or control medium.

Main Outcome Measure(s): Sperm kinematic and fertilizing parameters.

Result(s): Sperm hyperactivation was decreased in physiologic concentrations of ciprofloxacin hydrochloride and doxycycline hyclate over the course of 48 hours. At pharmacologic concentrations, ciprofloxacin hydrochloride, cefuroxime axetil, and nitrofurantoin monohydrate adversely affected motility with decreased rapid progression. Cessation of motility occurred in cefuroxime axetil and nitrofurantoin monohydrate. Sperm hyperactivation was also absent. Cefuroxime axetil decreased the percentage of intact acrosomes. In contrast, physiologic doses of ciprofloxacin hydrochloride or of ioxacin enhanced sperm fertilizing capacity.

Conclusion(s): Ciprofloxacin affected hyperactivation by altering membrane properties, whereas doxycycline inhibited the capacitation process. Cessation of motility in cefuroxime axetil was linked to disrupted sperm head membranes. Sperm motility and fertilizing capacity were decreased in nitrofurantoin because of decreased metabolism. The positive effect of of ioxacin on fertilizing capacity did not involve changes in acrosome.