A 47-year-old man presented with a “rash” for one month described as itchy and painful. It began at his head and spread downward to his torso (Figures 1-3). His PCP prescribed doxycycline and topical clindamycin with no improvement in symptoms.

Figure 1

Figure 2

Figure 3

Review Of Systems

Negative.

Medical History

Diabetes (25-year history)

Hypertension

Hospitalization for blood clot (2018)

Family History

Diabetes

Allergies

No known drug allergies.

Medications

Hydrochlorothiazide, Plavix, gabapentin, atorvastatin, metformin, glipizide, lisinopril, Lantus clindamycin gel

Physical Examination

Thick, greasy yellow scaly plaques present over face. Crusted ulcerations on scalp and torso. A few bullae located on chest. There were no oral lesions.

Labs

Non-fasting glucose elevated at 632mg/dL.

Culture of right cheek was negative.

PATHOLOGY

Two 3mm punch biopsies (bulla and perilesional) from the left chest were submitted for microscopic examination and direct immunofluorescent (DIF) studies. Histopathological exam revealed intraepidermal blister with prominent acantholysis. There were intercellular deposits of IgG and complement component C3 on DIF (Figures 4-5).

Figure 4

Figure 5

COURSE AND THERAPY

Patient presented to PCP with one-month history of lesions on head and torso. Doxycycline and topical clindamycin were prescribed without improvement, and patient was referred to dermatology. Patient was then prescribed doxycycline 100 mg BID, gentamycin ointment, and prednisone. Biopsies were performed and a diagnosis of pemphigus foliaceus was established based on histopathologic examination and DIF studies.

Patient was started on mycophenolate mofetil (CellCept, Genentech) 500mg BID for one week with plan to increase to 1000mg BID with repeat labs. At follow up patient had less scale and crusting, and no new lesions were identified.

DISCUSSION

Pemphigus foliaceus (PF) is an immunobullous disorder that presents with scaly and crusted lesions said to resemble “cornflakes” on an erythematous base, exfoliation, and flaccid bullae in a seborrheic distribution.1 Blisters are superficial and fragile and may be absent on exam. Additionally, oral lesions are rarely seen in this disease. Together these features contribute to frequent diagnostic delay.2 Patients complain of burning, pain, and puritis.1 While PF is less severe than other blistering disorders, significant morbidity and mortality results if left untreated.2

Pemphigus foliaceus most often affects patients between 40 and 50 years old, although it has been reported in children.1 Medications are thought to be the most common triggers for pemphigus initiation and flares. Increased susceptibility to pemphigus has been reported in patients with certain cancers and autoimmune diseases as well as those with a positive family history. Other triggers are thought to include allium vegetables, certain nutritional deficiencies, stress, radiation, pregnancy, and UV exposure.4

Blistering dermatoses are most often caused by an autoimmune reaction, and the pattern of deposition of immunoreactants seen on immunofluorescence exam as well as the histopathological features are key to establishing the correct diagnosis. Proper biopsy technique is essential for accurate results. DIF requires intact perilesional skin, avoiding the lower extremities when possible.1 Histopathological examination yields best results from biopsies of intact blisters that include the edge, but if no intact blisters are present, the edge of an erosion is acceptable.2

Pemphigus foliaceus demonstrates acantholysis of the upper epidermis on histopathological exam and intercellular IgG deposition throughout the epidermis on DIF.1,3 Usually a diagnosis of PF can be established with clinical presentation and biopsy results, though ELISA is available for detecting anti-Dsg1, the pathogenic autoantibody of PF that targets epithelial desmosomes, in complicated and atypical cases.3

Treatment for pemphigus foliaceus is similar to that of pemphigus vulgaris and includes two phases: induction of remission with steroids and maintenance of remission with adjuvant immunosuppressants.1 Combined therapies have not been shown to be more effective in complete response rate than glucocorticoids alone; however, adjuvant treatments may have a steroid-sparing effect, shorten time to sustained response, and delay relapse.5

Melchionda, V. and Harman K. E. (2019). Pemphigus vulgaris and pemphigus foliaceus: An overview of the clinical presentation, investigations, and management. Clin Exp Dermatol. doi:10.1111/ced.14041

James, W. D., Berger, T. G., and Elston, D. M. 2011. Andrew’s Diseases of the Skin: Clinical Dermatology (11th ed.). Saunders Elsevier.

Ohata, C., Ishii, N., and Furumura, M. (2014). Locations of acantholysis in pemphigus vulgaris and pemphigus foliaceus. J Cutan Pathol. Nov;41(11):880-9.

Tavakolpour, S. (2018). Pemphigus trigger factors: Special focus on pemphigus vulgaris and pemphigus foliaceus. Arch Dermatol Res. Mar;310(2):95-106.

Atzmony, L., Hodak, E., Gdalevich, M., Rosenbaum, O., and Mimouni, D. (2014). Treatment of pemphigus vulgaris and pemphigus foliaceus: A systematic review and analysis. Am J Clin Dermatol. Dec;15(6):503-15.