Treating Difficult Nails In Diabetic Patients
Due to the nature of the disease, the diabetic patient population has an increased risk of developing nail abnormalities, including onychocryptosis, onychomycosis and other nail structure malformations and injuries. Over one-third of diabetic patients suffer from nail abnormalities and are 2.77 times more likely to have nail mycoses compared to the general population.1 Diabetic patients often develop nephropathy, peripheral neuropathy, retinopathy, cardiovascular disease and impaired circulation, which further exacerbates secondary complications associated with various nail pathologies.2 Due to these sequelae of diabetes and the propensity of developing various nail disorders, the patient with diabetes has a higher risk for complications, including microbial invasion, infection, ulceration and injury. These risks make it important to recognize and treat nail disorders in the diabetic population.3 Mycotic nails can lead to adjacent nail, skin and subungual injury while providing reservoirs for various fungi and increasing the risk of other sequelae and infectious spread.2 The peripheral neuropathy that affects many patients with diabetes may delay recognition and treatment of minor abrasions and lesions. When these abrasions and lesions become infected, it can lead to further ulceration and propagation. Various onychopathies may affect the physical, mental and social health of the patient.4-5 Why It Is Important To Identify Nail Disorders In Patients With Diabetes Onychomycosis occurs in 5.9 percent of people with diabetes (20.8 million people in the United States) compared to 0.8 percent of people without diabetes.6,7 The secondary infection rate of diabetic patients with onychomycosis is 16 percent compared to 6 percent of those without onychomycosis.6 Patients with diabetes and onychomycosis also have a significantly higher occurrence of gangrene and foot ulceration (12.2 percent) as compared to diabetic patients without onychomycosis (3.8 percent).6 Diabetic foot screenings should include the evaluation of nail abnormalities, including onychocryptosis and onychomycosis. Complications of unmonitored nail disorders could lead to severe complications including ulceration and infection. Podiatric physicians should check for nail bed ulcerations resulting from subungual exostoses, distal osteochondromas and endchondromas. Treatment goals should emphasize prevention and active treatment of onychomycosis and other nail disorders in order to prevent associated morbidities and complications. Treatment options include mechanical intervention, pharmacological therapies and surgical intervention. Clinicians must first recognize the nail disorders. The clinical symptoms of onychomycosis include onycholysis, hyperkeratosis, brittle nails, paronychial inflammation and color changes.8 Tenderness to palpation directly on the nail plate in conjunction with associated deformity should trigger a radiographic evaluation of the distal phalanx to rule out exostoses, osteochondromas, endochondromas and suspected osteomyelitis in potential cases of nail bed ulcerations. After ruling out these osseous abnormalities, physicians should identify the causative pathogen. Identification begins with fungal culture or direct microscopy after KOH preparation. Direct visualization determines the presence of hyphal fragments but does not determine the exact organisms. However, results can certify dermatophytic or non-dermatophytic involvement.9 Differential diagnosis of pathogens causing onychomycosis include dermatophytes, non-dermatophytic molds and candidal species. Dermatophyte test media (DTM) can help confirm the clinical diagnosis but the most accurate diagnostic test is a histopathologic examination with periodic acid-Schiff stain (PAS), which has a reported 85 percent rate of accuracy.10 Key Diagnostic Considerations There are four types of fungal infection: distal subungual, white superficial, proximal subungual and candidal onychomycosis.11 Distal subungual onychomycosis, the most common infection, comprises 90 percent of all fungal occurrences. Trichophyton rubrum occurs most often.12 Distal subungual onychomycosis. Typically, distal subungual onychomycosis starts by invading the stratum corneum at the hyponychium or lateral nail folds. Superficial white onychomycosis. The second most common form of onychomycosis, superficial white onychomycosis accounts for approximately 10 percent of all nail mycoses. Trichophyton mentagrophytes, the pathogen responsible for superficial white onychomycosis, involves direct fungal invasion of the nail plate.12 Proximal subungual onychomycosis. This accounts for about 1 percent of all nail mycoses. T. rubrum causes the infection, which one generally sees in the immunocompromised patient.12 Candidal onychomycosis. Candidal onychomycosis is considered rare and represents less than 1 percent of infections. However, some studies report much higher incidences in the diabetic population. Gupta, et. al., found a 2.7 percent incidence rate among patients with diabetes.1 Studies have shown Candida species growing more readily on the stratum corneum of diabetic patients than on the same substrate in non-diabetic patients. This indicates a prevalence of the Candida species in those with diabetes.13-14 In general, T. rubrum and T. mentagrophytes account for more than 90 percent of all cases of onychomycosis.15 False negatives can occur with fungal culturing so clinicians should use their best judgment when it comes to dictating treatment in those cases. Although molds are rare, some studies have shown non-dermatophytic molds with a prevalence as high as 20 percent in diabetic nail infections. Typically, however, other primary, pathogenic fungi accompany the molds.16 The most common pathogenic molds are Scapularis brevicaulis, Fusarium species, Acremonium species, and Aspergillus species.17 Dermatophytes and the rare case of non-dermatophytic species consist of the majority of onychomycosis in patients with diabetes. Clinicians must consider many other causes of nail deformities and abnormalities in a differential diagnosis including psoriasis, lichen planus and yellow nail syndrome among others.18 Debridement And Topical Therapy: What You Should Know Onychomycosis is an infection. It is not merely a cosmetic problem. With the efficacy and safety of the newer pharmacologic agents, clinicians should no longer consider mechanical debridement to be a primary treatment option but more of an adjunctive therapy. Mechanical debridement helps by relieving the acute cause of painful, excessive focal pressure and other symptoms. It also helps to reduce the fungal bioburden and aids in managing the overall infection.19-20 While mechanical debridement does not treat the underlying pathogen and accordingly does not cure the infection, it does successfully augment pharmacological therapies targeting onychomycosis.21 The only FDA-approved topical therapy for onychomycosis is ciclopirox nail lacquer solution but this is only for mild to moderate nail infection not involving the lunula of the nail.22 Once-a-day application of ciclopirox for 48 weeks with recommended weekly debridements by the patient and monthly nail debridements by physicians can effectively treat the disorder. The ciclopirox solution penetrates all layers of the nail and associated structures.22 The mycological cure rates have been varied throughout the literature, ranging from 29 to 86 percent. However, a study by Gupta, et. al., in 2000 demonstrated cure rates in two randomized double-blind studies between 29 and 36 percent, with a cure rate defined as a negative KOH stain and fungal culture.23 The clinical cure rates, which represent a clinical cure by direct examination, are about one half of oral therapy cure rates. However, 90 percent of patients consider their onychomycosis improved after a full course of topical therapy.23 Ciclopirox has greater efficacy when one uses it in combination therapy rather than as a monotherapy.24 The vast majority of patients (99.5 percent) successfully tolerated the topical solution with minor, temporary adverse effects consisting of tingling and periungual erythema.22 Patients with dermatophytic nail infections who do not want or are not candidates for oral pharmacotherapy or surgical intervention may benefit from ciclopirox therapy. An Overview Of Oral Treatment Options For Onychomycosis Oral therapy has become the pharmacologic standard of care for treating onychomycosis. Podiatrists used griseofulvin, the first oral agent, for onychomycosis for over 30 years. However, it has since been replaced by the newer agents because of its limited use against dermatophytic infections, poor bioavailability, prolonged duration of therapy and fair efficacy with significant adverse effects and drug interactions.25 The FDA has not approved fluconazole for onychomycosis therapy but it works as an off-label therapy. One would administer fluconazole weekly based on its long half-life and it requires nine months of treatment duration.26 The most commonly used oral antifungals to treat onychomycosis are itraconazole and terbinafine. These medications help to eradicate the infection. One may utilize these medications via daily, continuous dosing for 12 weeks or in pulse-dosing regimens.11 Researchers have evaluated itraconazole and terbinafine in numerous comparative studies with two months of treatment duration. The studies demonstrated mycological cure rates ranging from 80 to 94 percent in the terbinafine group and between 54 and 75 percent in the itraconazole group.25,27 Comparison of the mycological cure rates did not show clinically significant differences between the two therapies. The use of these oral therapies has been demonstrated as effective and safe in patients with diabetes. Studies comparing terbinafine’s cure rates for diabetes type 1 and diabetes type 2 patients showed mycological cure rates of 71.1 and 75.7 percent respectively with no reported adverse effects or hypoglycemic episodes.28 Similar results have also been documented with itraconazole therapy in the diabetic population.29 Although itraconazole has a greater spectrum of activity, terbinafine appears to have high mycological cure rates (64 to 91 percent) for candidal onychomycosis.30 Although oral therapies effectively treat multiple etiologies of onychomycosis, there are patient safety concerns. Some of the more common, temporary side effects include gastrointestinal symptoms, vertigo, pruritic cutaneous reactions and cephalgia.31 Six percent of patients treated with terbinafine report temporary side effects such as green visual disturbances and metallic taste alterations.32 A 1997 study by Hall, et. al., involving 25,884 patients who used terbinafine, showed a 10 percent occurrence of mild and transient side effects.33 The study also involved 880 patients with diabetes. None of these patients had drug interactions or episodes of hypoglycemia.33 Itraconazole is metabolized by the cytochrome P450 system. Although some have raised concerns that the efficacy of other drugs (midazolam, quinidine, triazolam and HMG-CoA reductase inhibitors to name a few) metabolized by this system might be compromised, patients with diabetes have not shown an increased risk of adverse effects.29 Researchers have reported rare cases of liver failure and congestive heart failure.34 Simple liver function monitoring done prior to and at the midpoint of therapy can prevent serious complications and create a safe therapeutic experience for the patient. Exploring Options For Surgical Intervention Surgical management of difficult nails is appropriate for most patients with diabetes. However, many authors would disagree with the aggressiveness of these procedures. Therefore, candidates for surgical management include patients for whom oral agents are contraindicated or ineffective.37,38 Clinicians must use appropriate preoperative patient selection, especially with diabetic patients because of their potentially precarious vascular status. Diabetic patients with onychomycosis and associated onychocryptosis typically undergo partial nail avulsions to provide temporary relief of symptoms and for removal of the nidus causing infection.35 Patients may have total nail avulsions for symptomatic mycotic nails with or without associated infection. One can also perform avulsions in conjunction with oral and or topical treatment after removing the offensive, recalcitrant mycotic nail.35 In addition to oral therapy, one can also perform matrixectomies for severe cases of onychomycosis in patients with diabetes. A 1999 study by Felton, et. al., showed no statistical difference in the mean healing time of diabetic patients versus non-diabetic patients undergoing phenol and alcohol matrixectomies.36 People with diabetes undergoing chemical matrixectomies healed in 44 + 25 days on average, and non-diabetics healed in 43 + 24 days on average.36 The overall infection rate in those with diabetes was 10.3 percent and was 12.2 percent among non-diabetic patients.36 The study included three patients with non-palpable pulses, who took between 60 and 129 days to heal.36 A similar 1997 study by Giacalone showed a 7 percent infection rate for patients with diabetes. However, the study also stressed the importance of determining vascular status. Giacalone suggested that patients should have an ankle-brachial index (ABI) of at least 0.5 or higher and a toe pressure reading of at least 40 mmHg prior to performing permanent nail procedures.37 Applying adequate hemostasis during these procedures prevents potential bleeding from diluting the effects of the chemical ablation of the matrix. In regard to the chemical matrixectomy performed with phenol and followed by an alcohol rinse, this may cause further damage to the surrounding tissues, which can cause a delay in healing time, especially in those with diabetes.35 The alcohol does not neutralize the phenol but rather merely serves as a medium to flush out the excess acid. Since the alcohol rinse is an optional step in the chemical matrixectomy, patients with diabetes should not receive this portion of the treatment. Researchers have also suggested that one should apply porcine xenografts on nail beds following total nail avulsions and chemical matrixectomies in order to allow for better healing potential and permit better structure for the incoming nail.42 Surgical indications include chronic mycotic and dystrophic nails, failed phenol and alcohol procedures, scarred nail beds, hypertrophy of skin folds, immunosuppression or patients needing multiple procedures. The goals of surgical intervention include improved function, pain-free ambulation, a cosmetically pleasing appearance, limiting postoperative pain and limiting perioperative management. The advantages of surgical management over other means of intervention involve primary healing, decreased scar tissue, minimum perioperative management, predictable nail resection and the ability to apply sterile techniques. Surgical matrixectomy, another option for dealing with symptomatic and recalcitrant onychomycosis in the diabetic population, also requires appropriate patient selection. In some cases, severely deformed and symptomatic nails require surgical management secondary to onychomycosis despite the recent advance in pharmacological therapies.35 Partial surgical matrixectomies, such as the Winograd or Frost procedures, have limited use in this setting but are options if the situation dictates. What You Should Know About Nail Removal And Plastic Surgery Options Difficult, painful nails may dictate permanent total nail removal recalcitrant to other treatment modalities. The Zadik procedure facilitates direct visualization of the matrix with good skin coverage in difficult patients.35,40 The “H” type incisional approach allows access to underlying distal osseous pathology. Distal exostoses, osteochondromas and enchondromas may contribute to nail deformity. When this is the case, one must address these.35,40 Ungual phalanx disorders can cause nail pathology and symptomatology. The distal Symes procedure, a more radical approach for these types of nail and underlying osseous deformities, allows one to remove the nail bed, matrix, contiguous soft tissue structures and a portion of the distal phalanx.41 Clinicians can perform this procedure by making a transverse incision just proximal to the nail matrix but distal to the interphalangeal joint in order to preserve the articulation. The distal incision employs a fish-mouth type approach, allowing resection of the distal aspect of the phalanx and associated soft tissue structures. Create the plantar flap, advance it dorsally and coapt it to the proximal transverse incision. It is important not to leave bulky distal tissue in the plantar flap.41 Although the distal Symes procedure is a more radical procedure, it remains an effective treatment of recalcitrant and symptomatic onychopathy. Diabetic patients with viable perfusion to their respective digits may benefit from plastic reconstruction of nail bed deformities. Some options include local flaps, split-thickness skin grafts, cross-digit dermal grafts and reverse dermal grafts. In order to utilize these options, it is important to have a clear understanding of nail bed supply and associated angiosomes. Researchers have attributed the lunula’s coloration to poor blood supply overall in that specific area.43 The venous network coalesces in the proximal nail bed and in the skin proximal to the particular nail fold.43 Veins course in a random fashion over the dorsal aspect of the nail bed. The dorsal digital arteries terminate at the distal interphalangeal joint level dorsally while the plantar digital arteries terminate at the distal-dorsal aspect of the digit.44 By using angiosome principles of arterial-arterial connections, one can make safe incisions and raise local flaps to provide adequate soft-tissue coverage. Researchers have also described various skin plasties for nail deformities. Distal hallux converging, semi-elliptical skin incisions can help reduce clubbing deformities that often occur after nail loss.45 When Nail Trauma Is A Factor When it comes to patients with diabetes, nail trauma is common and secondary to neuropathy and onychopathy. Trauma disrupts blood vessels in the matrix and nail bed area, resulting in hematoma formation. If the hematoma is not permitted to drain, it can result in severe pain in the sensate individual. When 25 to 50 percent of the nail is involved, hematoma evacuation warrants plate removal, especially when there is nail bed laceration in the acute setting. Sterile needle decompression using an 18- to 22-gauge needle, trephination techniques or a fine point cautery device can effectively evacuate a hematoma.46 Warning signs of nail bed laceration include subungual hematoma involving greater than 25 to 50 percent of the nail unit and avulsion of the nail. Repair involves avulsion of the nail plate and careful inspection of the area. Small objects causing traumatic nail injury typically produce a splitting laceration while larger, blunt objects result in exploding or stellate injury patterns. Trimming irregular wound edges and undermining of the nail bed may reduce tension on the wound. A 6-0 or 7-0 absorbable suture should achieve closure. The original nail plate or a silicone sheath can cover the repaired wound. One can hold this in place with a suture on either side. Reapplying the nail plate or adding a silicone sheath in cases where the nail plate has been destroyed protects and splints the wound, helps shape the healing nail bed and prevents adhesions to the newly forming nail. Physicians must also look for fractures of the distal phalanx in these types of injuries and anatomically reduce the fracture to avoid nail bed deformity. The most successful procedure recreates a foundation or a flat scaffold for adherence of the regenerating nail. Final Words The diabetic patient population is prone to numerous nail disorders. By recognizing these disorders and instituting treatment, clinicians can help patients avoid harmful sequelae. When it comes to treating these nail disorders in patients with diabetes, one should consider aggressive treatment options based on careful patient selection. Many courses of therapy resolve onychopathy, infection and injury. Mechanical, pharmacological and surgical treatment options exist in order to provide the best outcomes based on individual patient selection. Dr. Blume is a Clinical Assistant Professor in the Department of Orthopaedics and Rehabilitation at the Yale University School of Medicine. He is also a Fellow of the American College of Foot and Ankle Surgeons, and is the Director of Limb Preservation at the Yale New Haven Hospital in New Haven, Conn. Dr. Wilkinson is a PGY-II resident at the Yale/VA-Connecticut Healthcare System. Dr. Key is an Associate of the American College of Foot and Ankle Surgeons. He is in private practice in New Haven, Ct. References 1. Gupta AK, et. al. Prevalence and epidemiology of toenail onychomycosis in diabetic subjects: a multicentre survey. Br J Dermatol 1998: 139: 665-71. 2. Rich P. Special Patient Populations: onychomycosis in the diabetic patient. J Am Acad Dermatol 1996: 35, S10-S12. 3. Gupta AK, et. al. The prevalance and management of onychomycosis in diabetic patients. Eur J Dermatol 2000; 10: 379-84. 4. Drake LA, et. al. Impact of onychomycosis on quality of life. J Am Podiatr Med Assoc 1997; 87:507-11. 5. Elewski BE, et. al. The effect of toenail onychomycosis on patient quality of life. Int J Dermatol. 1997; 36:754-56. 6. Boyko WL, et. al. Onychomycosis and its impact on secondary infection development in the diabetic patient population. 4th Annual International Meeting of the International Society for Pharmacoeconomics and Outcomes Research (ISPOR); May 23-26, 1999; 38:517-19. 7. American Diabetes Association. www.diabetes.org. 8. Tom CM, et. al. Management of toenail onychomycosis. Am J Health Systems Pharmacy. 1999; 56:865-71. 9. Elewski BE. Diagnostic techniques for confirming onychomycosis. J Am Acad Dermatol 1996; 35:56-59. 10. Lawry MA, et. al. Methods for diagnosing onychomycosis: a comparative study and review of literature. Archives of Dermatol 2000; 136:1112-6. 11. Robbins JM. Treatment of onychomycosis in the diabetic population. J Diabetes and Its Complications 2003; 17:98-104. 12. Zaias N, et. al. Diagnosing and Treating Onychomycosis. J Fam Practice 1996; 42(5):513-18. 13. Alteras I, et. al. Prevalence of pathogenic fungi in the toe-webs and toe-nails of diabetic patients. Mycopathologia 1979; 16:157-59. 14. Rurangirwa A, et. al. Growth of Candida Albicans on the stratum corneum of diabetic and non-diabetic patients. Mycoses 1990; 33:253-5. 15. Faergemann J, et. al. Epidemiology, clinical presentation and diagnosis of onychomycosis. Br J Dermatol 2003; 149(suppl):1-4. 16. Nandeelkar-Thomas MA, et al. An update on disorders of the nails. J Am Acad Dermatol 2000; 52(5):877-87. 17. Tosti A, et. al. Onychomycosis caused by non-dermatophytic molds: clinical features and response to treatment of 59 cases. J Am Acad Dermatol 2000; 42:217-24. 18. Luyten C, et. al. Yellow nail syndrome and onychomycosis. J Dermatol 1996; 192:406-8. 19. Markinson BC, et. al. Traditional approaches to treatment of onychomycosis. JAPMA 1997; 87:551-56. 20. Goldsmith H. Practice management and managed care issues in onychomycosis. JAPMA 1997; 87:532-39. 21. Joesph WS. Oral treatment options for onychomycosis. JAPMA 1997; 87:520-31. 22. Seebacher C, et. al. A multicenter, open label study of the efficacy and safety of ciclopirox nail lacquer 8% solution for the treatment of onychomycosis in diabetic patients. Cutis 2001; 68:17-22. 23. Gupta AK, et. al. Ciclopirox nail lacquer topical solution 8% in the treatment of onychomycosis. J Am Acad Dermatol 2000; 43:570-80. 24. Tan JS, et. al. Common fungal infections of the feet in patients with diabetes mellitus. Drugs Aging 2004; 21:101-12. 25. Elewski BE, et. al. Onychmycosis: pathogenesis, diagnosis, and management. Clinical Microbiology Reviews 1998; 11:415-429. 26. Kuokkanen K, et. al. Fluconazole in the treatment of onychomycosis caused by dermatophytes. J Dermatol 1993; 3:115-117. 27. Tosti A, et. al. Treatment of dermatophyte nail infections: an open randomized study comparing intermittent terbinafine therapy with continuous tebinafine treatment and intermittent itraconazole therapy. J Am Acad Dermatol 1996; 34:595-600. 28. Farakas B, et. al. Terbinafine treatment of toenail onychomycosis in patients with insulin-dependent and non-insulin-dependent diabetes mellitus: a multicentre trial. Br J Dermatol 2002; 146:254-260. 29. Albreski DA, et. al. The safety of itraconazole in the diabetic patient population. JAPMA 1999; 89:339-345. 30. Cribier B et. al. Terbinafine in the treatment of onychomycosis: a review of its efficacy in high risk populations and in patients with non-dermatophyte infections. Br J Dermatol 2004; 150:414-420. 31. Perfect JR, et. al. Adverse drug reactions to systemic antifungals. Drug Safety 1992; 7:323-363. 32. Steir DM, et. al. Patient satisfaction with oral verses non-oral therapeutic approaches in onychomycosis. JAPMA 2001; 91:521-527. 33. Hall M, et. al. Safety of oral terbinafine: results of post marketing surveillance study on 25,884 patients. Arch Dermatol 1997; 133:1213-1219. 34. FDA Public Health Advisory: www.fda.gov/cder/advisory/sporanox-lamisil/qa.htm. 35. McInnes BD, Dockery GL. Surgical treatment of mycotic toenails. JAPMA 1997; 87(12):557-564. 36. Felton PM, et. al. Phenol and alcohol chemical matrixectomy in diabetic versus non-diabetic patients. JAPMA 1999; 89(8):410-412. 37. Giacolone VF. Phenol matricectomy in patients with diabetes. JFAS 1997; 36:264. 38. Rich P, Hare A. Onychomycosis in a special patient population: focus on the diabetic. Int J Dermatol1999; 38(suppl 2):17-19. 39. Del Rosso JQ. Advances in the treatment of superficial fungal infections: focus on onychomycosis and digital tinea pedis. J Am Osteopath Assoc 1997; 97:339-346. 40. Dockery GL. McGlamry’s comprehensive textbook of foot and ankle surgery. 3rd ed. Philadelphia: Lippincott, Williams and Wilkins. 2001; vol 1 (ch. 7):203-230. 41. Dolce MD, et. al. The use of the distal syme’s procedure for treating onychopathy. Clin Podiatr Med Surg. 2004; 21:689-696. 42. Eleby DH, et. al. The use of porcrine xenografts on nail beds following total nail avulsion and phenol matrixectomy. J Foot Surg 1997; 63:85-91. 43. Wolfram-Gabel, et. al. Vascular networks of the periphery of the fingernail. J Hand Surg (Br.) 1995; 20(4):488-92. 44. Attinger CE, Cooper PS, Blume PA, et. al. The safest surgical incisions and amputations applying the angiosome principles and using the doppler to assess the arterial-arterial connections of the foot and ankle. Foot Ankle Clinics 2001; 6(4):745-800. 45. Bouche RT. Distal skin plasty of the hallux for clubbing deformity after total nail loss. JAPMA 1995; 85(1):11-14. 46. Palamarchuk HJ, et. al. An improved approach to evacuation of subungual hematoma. JAPMA 1989; 79(11);566-568.
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CE Exam #139 Choose the single best response to each question listed below. 1. What percentage of patients with diabetes has onychomycosis? a) 3.8 percent b) 5.9 percent c) 12.2 percent d) 16 percent 2. What pathogen causes superficial white onychomycosis? a) C. albicans b) T. rubrum c) S. aureus d) T. mentagrophytes 3. Which kind of onychomycosis accounts for 1 percent of all nail mycoses? a) Superficial white onychomycosis b) Proximal subungual onychomycosis c) Distal subungual onychomycosis d) Candidal onychomycosis 4. When used as a monotherapy, ciclopirox is … a) less effective than when it is used in combination therapy. b) more effective than when it is used in combination therapy. c) as effective as griseofulvin. d) as effective as itraconazole. 5. Although itraconazole has a greater spectrum of activity, ______ appears to have high mycological cure rates (64 to 91 percent) for candidal onychomycosis. a) fluconazole b) griseofulvin c) terbinafine d) ciclopirox 6. Diabetic patients undergoing permanent nail procedures should have a toe pressure reading of at least … a) 25 mmHg b) 30 mmHg c) 40 mmHg d) 45 mmHg 7. Diabetic patients with onychomycosis and associated onychocryptosis typically undergo a ________ for temporary symptom relief and for removal of the nidus causing infection. a) distal Symes procedure b) partial nail avulsion c) chemical matrixectomy d) none of the above 8. What are the indications for a surgical matrixectomy? a) Hypertrophy of skin folds b) Failed phenol procedure c) Chronic dystrophic nails d) All of the above 9. Which procedure allows one to remove the nail bed, matrix, contiguous soft tissue structures and a portion of the distal phalanx? a) Distal Symes procedure b) Zadik procedure c) “H” type incisional procedure d) Winograd procedure 10. Which condition is commonly secondary to neuropathy and onychopathy in patients with diabetes? a) Nail trauma b) Hematoma c) Subungual onychomycosis d) Onychocryptosis Instructions for Submitting Exams Fill out the enclosed card that appears on the following page or fax the form to NACCME at (610) 560-0502. Within 60 days, you will be advised that you have passed or failed the exam. A score of 70 percent or above will comprise a passing grade. A certificate will be awarded to participants who successfully complete the exam. Responses will be accepted up to 12 months from the publication date.