Cutaneous Conundrums, Dermatologic Disguises
Case 1:
A nonhealing ulcer recently developed in a painful facial rash that had worsened over several months. The 44-year-old patient is a heavy drinker with a history of elevated liver function levels. She has had numerous unprotected sexual contacts over the years An oral cephalosporin has had no effect on the facial eruption. The patient denies the use of other medications. Which of the conditions in the differential is the likely cause?A. Bacterial infection secondary to seborrhea.B. Squamous cell carcinoma.C. Bacterial infection secondary to rosacea.D. Deep fungal infection.E. Pyoderma gangrenosum.F. Factitial disorder. Which course of action do you pursue?G. Perform a bacterial culture.H. Perform a fungal culture.I. Determine the patient's HIV status.J. Obtain a hepatitis panel.K. Perform a skin biopsy.Case 2:
Neither oral terbinafine( nor oral itraconazole( resolved the white patch on a 62-year-old woman's fingernail. The condition, which first arose 3 months ago, causes slight, intermittent tenderness. The patient is otherwise healthy and takes no medications. What is the likely cause of this condition?A. Thyroid disease.B. Diabetes mellitus.C. Onychomycosis.D. Candida onycholysis.E. Psoriasis. To confirm your suspected diagnosis, you . . .F. Perform thyroid function tests.G. Obtain a serum glucose level.H. Perform a potassium hydroxide( evaluation.I. Perform a fungal culture.J. Perform a bacterial culture.Case 1:
Pyoderma gangrenosum, E,was a pathergic response to this patient's underlying sebopsoriasis. She was predisposed to this reactive process by hepatitis C; serologic testing was positive for anti-hepatitis C virus antibody, J. A skin biopsy, K, which ruled out a destructive skin cancer, deep infection, and factitial disease, supported the clinical impression. Prednisone( and anti-hepatitis C virus therapy were prescribed. The patient's condition improved steadily over several months. All of the diagnostic options are reasonable; however, bacterial infections generally are much more acute than this patient's disease. Deep fungal infections are indolent but rarely occur in an immunocompetent host. Rapid ulceration with associated pain is not typical of squamous cell carcinoma. Factitial disease is a consideration in this setting.Case 2:
Distal onycholysis, D, usually is caused by Candida species, which grew in the fungal culture, I, of a specimen obtained from this patient's fingernail. Most patients acquire the infection from excessive exposure to water; housecleaning and dishwashing are frequent causes. Although oral antifungal agents usually are effective, this patient's repetitive hand washing produced a favorable environment for reinoculation. The addition of a topical drying agent (4% thymol) to an oral antifungal agent, such as itraconazole, fluconazole(, or terbinafine, allows the nail to grow out reattached to the nail bed. Diabetes increases the risk of initial episodes and recurrences of onycholysis and onychomycosis. However, the involvement of only a single nail makes diabetes-as well as thyroid disease-unlikely. The pitting and oil-drop appearance of psoriasis-affected nails is not seen in this patient. The transverse ridging of the nail is attributable to trauma to the cuticle, not to the disease process. The thickened nail and subungual debris often seen in onychomycosis are absent here.Case 3:
A 37-year-old woman presents with her third episode in several months of a slightly tender rash on her trunk. She states that the eruption always looks the same, arises in the same location, and disappears after 2 to 3 weeks. The patient takes vitamins daily, antihistamines for seasonal allergies, and sulfa antibiotics for occasional urinary tract infections. What is the likely cause of the eruption?A. Pityriasis rosea.B.Tinea corporis.C. Psoriasis.D.Fixed drug reaction.E. Contact dermatitis. What therapy do you offer the patient?F. A corticosteroid cream.G.An antifungal cream.H.Calcipotriene cream.I. Change the antihistamine.J. Change the antibiotic.Case 3:
This rash is characteristic of a fixed drug reaction,D: circular, erythematous lesions that reappear in the same location after rechallenge with the same medication. The culprit here was the sulfa antibiotic, which was discontinued; a nonsulfa agent was substituted, J, and no additional eruptions occurred. Pityriasis rosea, tinea corporis, and psoriasis lesions do not come and go and are usually pruritic, not tender. Contact dermatitis, which can reappear after reexposure to the causative agent, typically is pruritic.Case 4:
A 12-year-old girl presents with a 3-month history of an itchy, bumpy rash on her legs; initially, it was thought to be eczema. When the outbreak did not respond to a potent topical corticosteroid, the patient was given ciclopirox(cream, but the antifungal offered no relief. What condition is responsible for the lesions?A. Psoriasis.B. Contact dermatitis.C. Nummular eczema.D. Impetigo.E. Dermatophyte infection. The potassium hydroxide (KOH) evaluation is negative; your next step is to . . .F. Perform a fungal culture.G. Perform a bacterial culture.H. Perform a skin biopsy.I. Initiate a trial of an oral antibacterial antibiotic.J. Initiate a trial of prednisone in a tapering dosage.K. Initiate a trial of an oral antifungal antibiotic.Case 4:
A deep dermatophyte infection,E, of a hair follicle, or Majocchi granuloma, produces an infectious folliculitis that is similar to tinea capitis. Unfortunately, a KOH evaluation is often negative; a skin biopsy, H, is needed to confirm the diagnosis. This condition usually arises as a result of occlusion, trauma or, as in this patient, shaving. Topical therapy is often ineffective, and systemic antifungal treatment is warranted. Contact dermatitis generally does not last for 3 months. Both nummular eczema and psoriasis are more scaly and respond to topical corticosteroids. Impetigo features crusting and is self-limited.Case 5:
A 48-year-old man presented with a painful rash on his neck of a few days' duration. Despite the patient's denial of trauma or bite, the initial impression was that of a brown recluse spider bite. A second group of vesicles in a similar distribution arose shortly after the first. Levofloxacin( and prednisone have been given for 2 days, but the rash remains. What do you suspect?A. Herpes simplex.B. Herpes zoster.C. Brown recluse spider bite that is unresponsive to the prescribed agents.D. Staphylococcal infection.E. Contact dermatitis. You prescribe which of the following?F. An antiviral agent to cover herpes simplex.G.An antiviral agent to cover herpes zoster.H.Dapsone.I. An oral cephalosporin.J. Another tapered course of prednisone.Case 5:
The appearance of a second group of vesicles on an erythematous base confirmed the clinical suspicion of herpes zoster, B; a solitary group of vesicles on an erythematous base can be either herpes simplex or herpes zoster. Typically, contact dermatitis is pruritic, not painful. Staphylococcal infections can be vesicular when impetiginous, but the vesicles are more fragile and more pruritic. Brown recluse spider bites are necrotic, not vesicular. This patient's eruption resolved after the antiviral agent famciclovir(, G, was given. Valacyclovir also offers good bioavailability and activity against herpes zoster and is another option in this setting.Case 6:
Three days ago, a 26-year-old woman was given levofloxacin for a mildly pruritic eruption on her posterior thigh. The rash had appeared a few days earlier after she had been in a hot tub. She seeks further evaluation because her symptoms have not abated. What are you looking at here?A. Partially treated hot tub folliculitis.B.Yeast folliculitis.C. Contact dermatitis.D.Impetigo.E. Herpes simplex. Your approach is to prescribe . . .F. Tetracycline(.G.A topical corticosteroid cream.H.Penicillin.I. A topical allylamine antifungal cream.J. A short tapered course of prednisone.Case 6:
The distribution of the rash suggests contact dermatitis, C, caused by something the patient sat on. A topical corticosteroid cream, G, resolved the eruption. Hot tub folliculitis presents with painful papules and pustules on the involved areas. The follicular papules and pustules of yeast folliculitis are more pruritic. Unlike the eruption seen on this patient, impetigo features crusted areas. The grouped vesicles on an erythematous base that characterize herpes simplex were absent here.
A nonhealing ulcer recently developed in a painful facial rash that had worsened over several months. The 44-year-old patient is a heavy drinker with a history of elevated liver function levels. She has had numerous unprotected sexual contacts over the years An oral cephalosporin has had no effect on the facial eruption. The patient denies the use of other medications. Which of the conditions in the differential is the likely cause?A. Bacterial infection secondary to seborrhea.B. Squamous cell carcinoma.C. Bacterial infection secondary to rosacea.D. Deep fungal infection.E. Pyoderma gangrenosum.F. Factitial disorder. Which course of action do you pursue?G. Perform a bacterial culture.H. Perform a fungal culture.I. Determine the patient's HIV status.J. Obtain a hepatitis panel.K. Perform a skin biopsy.Case 2:
Neither oral terbinafine( nor oral itraconazole( resolved the white patch on a 62-year-old woman's fingernail. The condition, which first arose 3 months ago, causes slight, intermittent tenderness. The patient is otherwise healthy and takes no medications. What is the likely cause of this condition?A. Thyroid disease.B. Diabetes mellitus.C. Onychomycosis.D. Candida onycholysis.E. Psoriasis. To confirm your suspected diagnosis, you . . .F. Perform thyroid function tests.G. Obtain a serum glucose level.H. Perform a potassium hydroxide( evaluation.I. Perform a fungal culture.J. Perform a bacterial culture.Case 1:
Pyoderma gangrenosum, E,was a pathergic response to this patient's underlying sebopsoriasis. She was predisposed to this reactive process by hepatitis C; serologic testing was positive for anti-hepatitis C virus antibody, J. A skin biopsy, K, which ruled out a destructive skin cancer, deep infection, and factitial disease, supported the clinical impression. Prednisone( and anti-hepatitis C virus therapy were prescribed. The patient's condition improved steadily over several months. All of the diagnostic options are reasonable; however, bacterial infections generally are much more acute than this patient's disease. Deep fungal infections are indolent but rarely occur in an immunocompetent host. Rapid ulceration with associated pain is not typical of squamous cell carcinoma. Factitial disease is a consideration in this setting.Case 2:
Distal onycholysis, D, usually is caused by Candida species, which grew in the fungal culture, I, of a specimen obtained from this patient's fingernail. Most patients acquire the infection from excessive exposure to water; housecleaning and dishwashing are frequent causes. Although oral antifungal agents usually are effective, this patient's repetitive hand washing produced a favorable environment for reinoculation. The addition of a topical drying agent (4% thymol) to an oral antifungal agent, such as itraconazole, fluconazole(, or terbinafine, allows the nail to grow out reattached to the nail bed. Diabetes increases the risk of initial episodes and recurrences of onycholysis and onychomycosis. However, the involvement of only a single nail makes diabetes-as well as thyroid disease-unlikely. The pitting and oil-drop appearance of psoriasis-affected nails is not seen in this patient. The transverse ridging of the nail is attributable to trauma to the cuticle, not to the disease process. The thickened nail and subungual debris often seen in onychomycosis are absent here.Case 3:
A 37-year-old woman presents with her third episode in several months of a slightly tender rash on her trunk. She states that the eruption always looks the same, arises in the same location, and disappears after 2 to 3 weeks. The patient takes vitamins daily, antihistamines for seasonal allergies, and sulfa antibiotics for occasional urinary tract infections. What is the likely cause of the eruption?A. Pityriasis rosea.B.Tinea corporis.C. Psoriasis.D.Fixed drug reaction.E. Contact dermatitis. What therapy do you offer the patient?F. A corticosteroid cream.G.An antifungal cream.H.Calcipotriene cream.I. Change the antihistamine.J. Change the antibiotic.Case 3:
This rash is characteristic of a fixed drug reaction,D: circular, erythematous lesions that reappear in the same location after rechallenge with the same medication. The culprit here was the sulfa antibiotic, which was discontinued; a nonsulfa agent was substituted, J, and no additional eruptions occurred. Pityriasis rosea, tinea corporis, and psoriasis lesions do not come and go and are usually pruritic, not tender. Contact dermatitis, which can reappear after reexposure to the causative agent, typically is pruritic.Case 4:
A 12-year-old girl presents with a 3-month history of an itchy, bumpy rash on her legs; initially, it was thought to be eczema. When the outbreak did not respond to a potent topical corticosteroid, the patient was given ciclopirox(cream, but the antifungal offered no relief. What condition is responsible for the lesions?A. Psoriasis.B. Contact dermatitis.C. Nummular eczema.D. Impetigo.E. Dermatophyte infection. The potassium hydroxide (KOH) evaluation is negative; your next step is to . . .F. Perform a fungal culture.G. Perform a bacterial culture.H. Perform a skin biopsy.I. Initiate a trial of an oral antibacterial antibiotic.J. Initiate a trial of prednisone in a tapering dosage.K. Initiate a trial of an oral antifungal antibiotic.Case 4:
A deep dermatophyte infection,E, of a hair follicle, or Majocchi granuloma, produces an infectious folliculitis that is similar to tinea capitis. Unfortunately, a KOH evaluation is often negative; a skin biopsy, H, is needed to confirm the diagnosis. This condition usually arises as a result of occlusion, trauma or, as in this patient, shaving. Topical therapy is often ineffective, and systemic antifungal treatment is warranted. Contact dermatitis generally does not last for 3 months. Both nummular eczema and psoriasis are more scaly and respond to topical corticosteroids. Impetigo features crusting and is self-limited.Case 5:
A 48-year-old man presented with a painful rash on his neck of a few days' duration. Despite the patient's denial of trauma or bite, the initial impression was that of a brown recluse spider bite. A second group of vesicles in a similar distribution arose shortly after the first. Levofloxacin( and prednisone have been given for 2 days, but the rash remains. What do you suspect?A. Herpes simplex.B. Herpes zoster.C. Brown recluse spider bite that is unresponsive to the prescribed agents.D. Staphylococcal infection.E. Contact dermatitis. You prescribe which of the following?F. An antiviral agent to cover herpes simplex.G.An antiviral agent to cover herpes zoster.H.Dapsone.I. An oral cephalosporin.J. Another tapered course of prednisone.Case 5:
The appearance of a second group of vesicles on an erythematous base confirmed the clinical suspicion of herpes zoster, B; a solitary group of vesicles on an erythematous base can be either herpes simplex or herpes zoster. Typically, contact dermatitis is pruritic, not painful. Staphylococcal infections can be vesicular when impetiginous, but the vesicles are more fragile and more pruritic. Brown recluse spider bites are necrotic, not vesicular. This patient's eruption resolved after the antiviral agent famciclovir(, G, was given. Valacyclovir also offers good bioavailability and activity against herpes zoster and is another option in this setting.Case 6:
Three days ago, a 26-year-old woman was given levofloxacin for a mildly pruritic eruption on her posterior thigh. The rash had appeared a few days earlier after she had been in a hot tub. She seeks further evaluation because her symptoms have not abated. What are you looking at here?A. Partially treated hot tub folliculitis.B.Yeast folliculitis.C. Contact dermatitis.D.Impetigo.E. Herpes simplex. Your approach is to prescribe . . .F. Tetracycline(.G.A topical corticosteroid cream.H.Penicillin.I. A topical allylamine antifungal cream.J. A short tapered course of prednisone.Case 6:
The distribution of the rash suggests contact dermatitis, C, caused by something the patient sat on. A topical corticosteroid cream, G, resolved the eruption. Hot tub folliculitis presents with painful papules and pustules on the involved areas. The follicular papules and pustules of yeast folliculitis are more pruritic. Unlike the eruption seen on this patient, impetigo features crusted areas. The grouped vesicles on an erythematous base that characterize herpes simplex were absent here.
References