1. Onychomycosis
Hai Ho, M.D.

2. Psoriasis Diagnosis? Pitting Nail involvement – 10-50%
Usually along with skin lesions, but could be alone
Could occur in eczema, fungal infection, and alopecia areta
Pitting – abnormal shedding as psoriatic scales
Psoriasis

3. Psoriasis Diagnosis? Pitting Onycholysis
Yellow psoriatic debris under the nail causing nail separation
Pitting and onycholysis
Psoriasis

4. Diagnosis? Psoriasis Nail matrix involvement leading to nail deformity
Plate alteration
Psoriasis

5. Diagnosis? Onycholysis
Painless separation of the nail from the nail bed
Causes: trauma (long nail in women), hyperthyroidism, prolonged immersion, psoriasis
Consider TSH in asymptomatic patient

6. Traumatic onycholysis
Diagnosis?
Traumatic onycholysis

7. Onycholysis May have secondary candida infection Treatment
Avoid long nail
Tinture containing miconazole under nail
Fluconazole for resistant case

8. Diagnosis? Nail hypertrophy
Cause: tight-fitted shoes or chronic trauma
Treatment: filing or removing the nail with phenol

9. Diagnosis? Leukonychia punctata
Cause by cuticle manipulation or other mild trauma

10. Diagnosis?
Leukonychia

11. Diagnosis? Distal splitting nail Analogous to peeling of dry skin
Affected 20% of adults
Associated with water immersion and use of polish remover
Treatment
Moisturizer
B-complex vitamin biotin (2.5mg/day) for brittle nail

12. Diagnosis? Pincer nail Due to ?tight shoes Treatment Nail removal
Reconstruction of nail unit

13. Habit-tic onycholysis
Diagnosis?
Habit-tic onycholysis

14. Diagnosis?
Median dystrophy

15. Moral of the story
Cannot diagnose onychomycosis by visualization alone
>50% of fungal-looking nail do not have fungal infection

16. Common organisms in onychomycosis?
Dermatophytes
Trichophytum rubum
Trichophytum mentagrophytes
Contaminants or nonpathogens
Aspergillus, Cephalosporium, Fusarium, and Scopulariopsis

17. Patterns of infection

18. Distal subungual onychomycosis
Most common
Fungi invade the hyponychium and grow in the substance of nail plate, causing it to crumble
Hyperkeratotic debris causes nail to separate from the bed

19. Distal subungual onychomycosis
Linear channel
Infection advance proximally
Characteristic feature of fungal infection

20. White superficial onychomycosis
Commonly Trichophyton mentagrophytes
Nail - white, soft, powdery

21. White superficial onychomycosis
Nail
not thickened
not separated from the nail bed

22. Proximal subungual onychomycosis
Commonly Trichophyton Rubrum
Invade the substance of nail plate, not the surface
Hyperkeratotic debris causes the nail plate to separate from the nail bed

23. Proximal subungual onychomycosis is associated with what disease?
HIV

24. Candida onychomycosis
Almost exclusively in chronic mucocutaneous candidiasis
Generally infect all fingernails
Linear yellow or brown streaks grow and advance proximally

25. Candida onychomycosis
Yellow areas with hyperkeratosis

26. Laboratory tests?
KOH – improve detection with fluorochrome which binds with chitin in fungal cell wall and fluoresces
Culture – gold standard
Histological examination by periodic acid-Schiff (PAS) staining – equal to culture

27. Obtaining specimen Clip the nail for PAS & culture
Subungal debris for KOH & culture
Fungi reside in the nail plate and cornified cells in the nail bed
Hyphae in the nail plate may not be viable, so obtain specimen from nail bed for culture

28. KOH examination
Hard nail plate and debris could be softened overnight with KOH
Artifacts – lipid droplet between cells; eliminated by heat which separates cells

29. Culture Sabouraud's with antibiotics ID the organism
Antibiotics suppress bacterial contaminants
Medium turn from yellow to red in 7-14 days – alkaline released by dermatophytes turn phenol (pH indicator) red
ID the organism
Some nondermatophytes, such as Scopulariopsis, Aspergillus, Penicillium, black molds, and yeast, may cause a color change and give a false-positive reaction.
The dermatophyte test medium contains the antibiotic cycloheximide and phenol red as a pH indicator. Dermatophytes release alkaline metabolites that turn the medium from yellow to red in 7 to 14 days. Some nondermatophytes, such as Scopulariopsis, Aspergillus, Penicillium, black molds, and yeast, may cause a color change and give a false-positive reaction.

30. PAS staining
In the presence of periodic acid, hydroxyl group of polysaccharide in fungal cell wall oxidized to aldehyde
Schiff reacts with aldehyde to stain fungal elements pinkish-red
False-negative – sampling error
Alan Woodgyer, mycology scientist and Dr Geoff Hogg Fellow of the Royal College of Pathologists of Australasia
(First appeared in Medical Observer Weekly 10/10/04)

31. Treatment

32. Options Systemic – terbinafine, itraconazole, fluconazole Topical
Mechanical

33. Terbinafine is more effective than itraconazole and fluconazole
Oral medications
Terbinafine is more effective than itraconazole and fluconazole

34. Terbinafine vs. intermittent itraconazole
Cure rate at 72 weeks
Crawford F, et al. Arch Dermatol 2002; 138:811

35. Terbinafine vs. fluconazole
Cure rate at 60 weeks
Havu V, et al. Br J Dermatol 2000; 142(1):97.

36. Ineffective oral regimen
Intermittent terbinafine
Greseofulvin

37. Regimen Drug Dosage Fluconazole (Diflucan)
One 150-mg dose each week for 9 months
Itraconazole (Sporanox)
200 mg/day for 12 weeks for toenails, 6 weeks for fingernails “Pulse dosing”: 400 mg/day for first week of each month Fingernails 2–3 pulses Toenails 3–4 pulses
Terbinafine
250 mg/day (12 weeks for toenails, 6 weeks for fingernails)

38. Adverse effect of terbinafine?
Cholestatic hepatitis and blood dyscrasias
LFT and CBC prior to and at 6 weeks during treatment
Discontinue if AST/ALT >2x normal. Am Fam Physician 2001;63:663-72,677-8

39. Adverse effect of itraconazole?
Hepatitis for continuous but not intermittent regimen
LFT prior and at 6 weeks during treatment for continuous, not pulse, regimen
Am Fam Physician 2001;63:663-72,677-8

40. Drug interactions with itraconazole
Cytochrome P450 system
Arrhythmia with quinidine and primozile
Rhabdomyolysis with HMG-CoA reductase inhibitors, such as atorvastatin
Sedation and apnea with benzodiazepines
Decrease absorption with high gastric pH
Avoid H2-blocker and PPI
Take with food
Am Fam Physician 2001;63:663-72, Primozile – antipsychotics.

41. Fluconazole Not FDA approval for onychomycosis
First line for candida but could use for dermatophytes
Check LFT
Am Fam Physician 2001;63:663-72,677-8

42. Prevent recurrence
Prevent tinea pedis – powder to feet, protect feet in communal shower, change socks
Avoid trauma by tight shoes
Ciclopirox nail lacquer 8% (PENLAC) 2 to 3 times a week
Topical treatment up to a year to prevent recurrence.

43. Ciclopirox nail lacquer 8% (PENLAC)
Cure rate at 48 weeks – 29%
Apply to affected nail and 5 mm of surround skin daily
Remove PENLAC with alcohol weekly
Remove infected nail frequently

44. Mechanical removal Surgery
Nonsurgical avulsion of dystrophic nail, not normal one
The technique removes only grossly diseased or dystrophic nails, not normal nails. Forty percent urea gel (Carmol-40 gel, Vanamide cream) is commercially available or by prescription.
Cloth adhesive tape is used to cover the normal skin surrounding the affected nail plate, which has been pretreated with tincture of benzoin. The urea cream is generously applied directly to the nail surface and covered with a piece of plastic wrap. This in turn is covered with a finger that is cut from a plastic glove and held in place with adhesive tape. Patients are instructed to keep the area completely dry with the aid of plastic gloves or booties.

45. Nonsurgical avulsion
Apply 40% urea gel (Carmol-40 gel, Vanamide cream) with occlusive dressing
Remove the entire nail or cut the affected portion, followed by curetting to normal nail in 7-10 days
Cloth adhesive tape is used to cover the normal skin surrounding the affected nail plate, which has been pretreated with tincture of benzoin. The urea cream is generously applied directly to the nail surface and covered with a piece of plastic wrap. This in turn is covered with a finger that is cut from a plastic glove and held in place with adhesive tape. Patients are instructed to keep the area completely dry with the aid of plastic gloves or booties.

46. The End