Wednesday, September 30, 2009

Atypical plaque on the hand

Submitted by Dr Henry Foong, Ipoh, Malaysia

An 80-year-old retired goldsmith presented with 4-month history of an ulcerated plaque on the left hand. It had gradually increased in size. His past medical history included hypertension, diabetes mellitus, and ischemic heart disease. His medications included norvasc, zocor, ticlid and amaryl.

Examination of the skin showed a localized ulcerated verrucous plaque 6 x 6 cm on the dorsum of the left hand. Closer examination showed slough and blackish dots on the surface of the plaque. Regional nodes were not enlarged.

Our presumptive diagnosis is either atypical mycobacterium infection or chromoblastomycosis.

The epithelium shows pseudoepitheliomatous hyperplasia. The upper dermis is densely infiltrated by acute and chronic inflammatory cells. Neutrophils are also noted in the lining epithelium. No granulomas or Langhan's giant cells are seen. No microorganisms are noted. Negative for dysplasia and malignancy. Ziehl-Neelsen stain for acid fast bacilli is negative. Periodic acid Schiff stain for fungi is negative. Culture for AFB and fungal organism were negative

He was initially treated with itraconazole 100mg bd and after 2 weeks there was no improvement at all. Bactrim 2 tab daily was added and this time it showed improvement after 2 weeks of the combination.

One of the differential that was considered is pustular vasculitis or neutrophilic dermatosis of the dorsum of the hands. Points supporting this diagnosis include pseudoepitheliomatous hyperplasia and the absences of granuloma on histology examination.

I suspect this could be atypical mycobacterium infection based on the empirical therapeutic response to bactrim. I wonder what your views are with regard to this case?


  1. This is an interesting case. In the DDX, I would consider neutrophilic dermatosis of the dorsal hands. There are some good reviews in the literature. NDDH may be a variant of Sweet's syndrome. Therefore, prednisone may help or even SSKI. You are right to keep thinking of deep fungal or atyp AFB and these are difficult to rule out.

  2. To my mind the lesion was similar to lesions of Cutaneous leishmaniasis, that we see in India. The plaque on the exposed site/ unilateral distribution/ erythematous ring around the plaque/ ulceration and crusting/ biopsy is showing some plasma cells too.
    Atypical mycobacteria is a good possibility too.
    I would do rK 39 antigen and culture for leishmaniasis too, along with Bactec and Real time PCR for Mycobacteria.
    If nothing works atrial of miltefosine / Anti tubercular Rx with clarithromycin may be tried.
    Thanks for a thought provoking case.
    Dr Manish Pahwa
    New Delhi

  3. Amit PandyaOctober 01, 2009

    If repeated tissue cultures and special stains are negative, I would treat as pyoderma gangrenosum. Systemic steroids, dapsone and/or TNF inhibitors should help. I would avoid cyclosporine because of his age (compromised renal function).

  4. Nidal Obaidat, JordanOctober 01, 2009

    My favored diagnosis is neutrophilic dermatosis of the dorsal hands. this is considered by many as variations of pyoderma gangrenosum, Sweet syndrome or pustular vasculitis. If a deep infective process is still a possibility, I think that dapsone is preferred over others. The patient should also be screened for possible underlying causes, such as lymphoproliferative disorders, other malignancies, rheumatological diseases, and lastly possibly as a drug reaction!

  5. I beleieve Cutaneous leishmaniasis should be given a consideration. It can be confirmed with simple tests like smear with leishmanin stain.

  6. Ashok Kumar SharmaOctober 02, 2009

    Clinically, I would agree with the 2 possibilities of Atypical mycobacterial infection or Chromomycosis. Clinically from the morphology of the lesion, I do not agree with the possibilities of Leishmaniasis or Pyoderma gangrenosum.
    The patient has been on some anti-infective treatments so the results of tests (smears/cultures)could be unreliable. But still I would suggest repeat smears and cultures.
    As far as treatment is concerned as there is some response to Bactrim, the same could be continued for a prolonged period, maybe 3 months or more. Let us not forget that a prolonged course of antimicrobials is common in deep mycoses.


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