CONTINUING MEDICAL EDUCATION Onchocerciasis (River Blindness) Capt Lance H. Borup, USAF, MC; MAJ John S. Peters, MC, USA; Lt Col Christopher R. Sartori, USAF, MC GOAL To gain a thorough understanding of onchocerciasis OBJECTIVES Upon completion of this activity, dermatologists and general practitioners should be able to: 1. Explain the cutaneous and systemic manifestations of onchocerciasis. 2. Discuss the infection process of onchocerciasis. 3. Describe the treatment for onchocerciasis. CME Test on page 296. This article has been peer reviewed and is accredited by the ACCME to provide continuing approved by Michael Fisher, MD, Professor of medical education for physicians. Medicine, Albert Einstein College of Medicine. Albert Einstein College of Medicine designates Review date: September 2003. this educational activity for a maximum of 1 This activity has been planned and implemented category 1 credit toward the AMA Physician’s in accordance with the Essential Areas and Policies Recognition Award. Each physician should claim of the Accreditation Council for Continuing Medical only that hour of credit that he/she actually spent Education through the joint sponsorship of Albert in the activity. Einstein College of Medicine and Quadrant This activity has been planned and produced in HealthCom, Inc. Albert Einstein College of Medicine accordance with ACCME Essentials. Drs. Borup, Peters, and Sartori report no conflict of interest. The authors report no discussion of off-label use. Dr. Fisher reports no conflict of interest. A 37-year-old African man presented for excision microfilariae. The patient was admitted to the of a dermal nodule after a diagnosis of ocular hospital and treated with one dose of ivermectin. onchocerciasis (river blindness). A nodule from Recommendations were made for ivermectin the patient’s left buttock contained several adult treatments every 6 months for up to 10 years. filarial worms, and results from adjacent skin The history, clinical presentation, diagnosis, and biopsy specimens revealed numerous dermal treatment of onchocerciasis are discussed. Cutis. 2003;72:297-302. Accepted for publication July 31, 2003. nchocerciasis (river blindness) is an infec- Dr. Borup is a resident at Osteopathic Medical Center of Texas, tious disease common in west and central Fort Worth. Dr. Peters is Chief of the Dermatology Clinic, Martin Africa, Central and South America, and Army Community Hospital, Fort Benning, Georgia. Dr. Sartori is O Associate Clinical Professor of Dermatology at the University of the Arabian Peninsula. Onchocerciasis is the sec- Colorado School of Medicine, Denver, and Chief of the ond leading infectious cause of blindness world- Dermatology Clinic, United States Air Force Academy wide. Approximately 18 million people are Hospital, Colorado Springs, Colorado. infected with Onchocerca volvulus, of which 99% The opinions expressed are those of the authors and do not 1 necessarily state or reflect those of the US military. are in Africa. O volvulus is a filarial nematode, the Reprints: Capt Lance H. Borup, USAF, MC, 7341 Moon Ridge Ct, etiologic agent of onchocerciasis. The most com- Fort Worth, TX 76133 (e-mail: [email protected]). mon cutaneous manifestations of onchocerciasis VOLUME 72, OCTOBER 2003 297 Onchocerciasis are intense pruritus, subcutaneous nodules, and for 6 months. The patient denied any history of localized erythematous papules and plaques with surgery. He had no known drug allergies, and his induration. Ocular pathology in onchocerciasis only medications were ophthalmic timolol, manifests as uveitis, punctate keratitis, and glau- latanoprost, and dorzolamide. The remainder of his coma. Diagnosis is made through slitlamp examina- review of systems was unremarkable. tion, as well as by demonstration of filarial worms The patient was of normal height and weight, on wet mount and hematoxylin-eosin (H&E) alert and oriented, and in no acute distress. Bilat- stained sections. Patients are treated with oral or eral conjunctival injection without drainage or intravenous ivermectin at a dose of 150 mg/kg once exudate was noted. Results of a cutaneous exami- every 6 months for up to 10 years.2 nation revealed 2 soft, mobile, nontender masses. We present the case of a US Army soldier origi- One mass in the left axilla was superficial and mea- nally from west Africa who was initially treated sured 1.5 cm in diameter, while the other in the left over a period of 2 years for conjunctivitis, uveitis, buttock was deeper in the dermis and measured and a labile refractory glaucoma. After referral to 3.0 cm in diameter. No lymphadenopathy or edema ophthalmology and dermatology, a diagnosis of was detected. No acute or chronic papular dermati- onchocerciasis was made. tis, excoriations, lichenifications, fine wrinkles, or depigmentation characteristic of onchocerciasis Case Report were appreciated. A 37-year-old African man presented to the glau- Laboratory test results for liver function, pro- coma clinic for evaluation of refractory glaucoma in thrombin time, international normalized ratio, par- his right eye and for possible trabeculectomy. Numer- tial thromboplastin time, and chemistry panel were ous microfilariae were noted in the anterior chamber within normal limits. The complete blood count of both eyes on slitlamp examination. The diagnosis demonstrated a mild eosinophilia of 8.6%. Hepati- of onchocerciasis was made, and the patient was tis panel was consistent with a chronic carrier state referred to the infectious diseases clinic, where fur- for subdeterminants of hepatitis B surface antigen ther examination revealed subcutaneous nodules in (ϩ), hepatitis B surface antibodies (Ϫ), and hep- his left buttock and left axilla. He then was referred atitis B e antigen (Ϫ). Thick and thin peripheral to dermatology. blood smears performed in the afternoon and at The patient was a poor historian and spoke midnight showed no other parasitic infections. limited English. His medical history was signifi- Excisional biopsy of the nodule in his buttock was cant for ongoing flares of bilateral conjunctivitis performed and yielded a 1ϫ2-cm diameter mass of and chronic uveitis. Originally from Sierra Leone, fatty tissue with intertwined, white, hairlike worms west Africa, he emigrated to the United States encased in a thick fibrous capsule (Figure 1). The with his family 3 years previously and thereafter number of worms in the nodule and their lengths enlisted in the US Army. The patient reported were not determined. Excisional biopsy of the axillary intermittent blurred vision for many years and mass was performed, and results revealed a steatocys- episodes of severely irritated watery eyes. He had toma on standard H&E sections. Perilesional skin no current complaints of rash or pruritus, but as a snips also were obtained. younger man he remembered having intermittent Paraffin sections of an adult worm were prepared, pruritus in his left inguinal area and in both eyes. placed on glass slides, and viewed at ϫ100 magnifi- He denied ever having a rash or other skin dis- cation (Figure 2). Histopathology was typical of sub- coloration. His wife also complained of visual cutaneous nodules, with outer walls of dense fibrous problems. He also recalled that in his village of tissue extending between the worms. Skin biopsy Sierra Leone, most elderly people were blind. His specimens extending just into the dermis were 2 children, who were born in Sierra Leone, also obtained from the left buttock, embedded into paraf- reported a history of pruritic skin and blurry fin, and stained with H&E (Figure 3). Eosinophils vision but were currently asymptomatic. were present around degenerating microfilariae. Two years before presentation, the patient was Progressive fibrosis of the dermis was present, and the diagnosed with primary open-angle glaucoma. He epidermis showed acanthosis and hyperkeratosis. had experienced atypical exacerbations and remis- The patient was admitted to the hospital, sions. He reported right temporal field visual loss treated intravenously with one dose of ivermectin and cloudy vision bilaterally for 5 years. In addi- 10,000 mg (150 mg/kg), and monitored overnight. tion, he had a history of hepatitis B, malaria, and a To prevent a hypersensitivity reaction secondary to positive purified protein derivative (tuberculin) massive microfilarial death, he was treated orally skin test, for which he was treated with isoniazid with both 25 mg of diphenhydramine every 6 hours 298 CUTIS® Onchocerciasis Figure 1. Buttock nodule (onchocercoma) containing fatty tissue with intertwined, white, hairlike worms. and 25 mg of hydroxyzine, as needed, for itching. response, which is responsible for the majority of The patient tolerated the treatment well and was clinical symptoms.6 The initial dermatologic pre- told he should be treated with ivermectin biannu- sentation includes intense pruritus, subcutaneous ally for the next several years. He was discharged nodules, and localized discrete papules or plaques the following day. with erythema and induration. Chronic skin changes include areas of hyperpigmentation and Comment hypopigmentation (“leopard skin”) and lichenifica- O volvulus is 1 of 8 filarial nematodes that can infect tion. The cutaneous inflammatory response to the humans and is endemic to west and central Africa, microfilariae leads to breakdown of dermal collagen Central and South America, and the Arabian and elastic tissue. The skin becomes progressively Peninsula (Figure 4). It is estimated