Hyperosmolar Sexual Lubricant Causes Epithelial Damage in the Distal Colon: Potential Implication for HIV Transmission

• Published in: The Journal of infectious diseases 2007-03, Vol.195 (5), p.703-710
• Main Authors: Fuchs, Edward J., Lee, Linda A., Torbenson, Michael S., Parsons, Teresa L., Bakshi, Rahul P., Guidos, Anita M., Wahl, Richard L., Hendrix, Craig W.
• Format: Article
• Language: English
• Subjects: Antiinfectives; Biological and medical sciences; Biopsies; Colon - drug effects; Colon - pathology; Cross-Over Studies; Enema; Fundamental and applied biological sciences. Psychology; Gels; Gels - administration & dosage; Gels - adverse effects; Gels - chemistry; HIV; HIV infections; HIV Infections - transmission; HIV/AIDS; Human immunodeficiency virus; Humans; Infectious diseases; Intestinal Mucosa - drug effects; Intestinal Mucosa - pathology; Isotopes; Lubricants; Lubrication; Male; Medical sciences; Microbiology; Miscellaneous; Mucosa; Osmolar Concentration; Sigmoidoscopy - adverse effects; Urine; Virology
• ISSN: 0022-1899; 1537-6613
• DOI: 10.1086/511279

Background. Many sexual lubricants are hyperosmolar. Hyperosmolar enemas induce epithelial damage, and enema use has been associated with an increased risk of HIV infection. To inform the development of rectal microbicide formulation, we evaluated the effects of hyperosmolar gels on the rectal mucosa. Methods. Two commercial lubricants were compounded into iso-osmolar and hyperosmolar mixtures (283 and 3429 mOsm/kg, respectively). Each gel was radiolabeled with 500 µCi of 99mTechnetium-diethylene triaminepentaacetic acid, and 10 mL was given rectally to 10 subjects in random sequence. Sigmoidoscopy by an endoscopist blinded to treatment assignment was performed 90 min later to obtain luminal and mucosal samples. Urine radiolabel detection was used to assess mucosal permeability. Results. Epithelial denudation 10 cm from the anus occurred to a greater degree with the hyperosmolar gel than with the iso-osmolar formulation (median toxicity grade, 2.50 vs. 1.17 out of 3, respectively; P=.009). The hyperosmolar gel was also associated with lower isotope luminal concentration at 10 cm, compared with the isoosmolar gel (median, 8.9% vs. 54.6% of administered concentration, respectively). Mucosal permeability measured through 12 h was reduced with the hyperosmolar gel (P=.037). Conclusion. Rectally applied hyperosmolar gels induce greater epithelial denudation and luminal secretion than iso-osmolar gels. Because denudation plausibly increases the risk of HIV transmission, hyperosmolar gels make poor rectal microbicide formulations, and hyperosmolar sexual lubricants may increase susceptibility to HIV infection.