Pustular-vesicular lesions on extremities, trunk in infant female

A 1-year-old female is referred for admission to the hospital for the evaluation of fever and a rash. The patient’s past history is positive for an acute hematologic malignancy with relapse. It was noted about 1 week prior to admission that the patient had some mildly painful bumps appearing on her extremities. The parents thought this to be a heat rash at first, but when it persisted along with the development of some fever, definitive evaluation was sought. Exam revealed a fever of 101.5°F, with the skin revealing numerous scattered pustular-vesicular lesions on her extremities and trunk as shown (Figures 1-3).

The lesion marked with a circle was biopsied and stained for histopathology, bacteria and fungi, revealing only dense neutrophilic infiltration of the dermis (Figure 4) without evidence of vasculitis and a negative Tzanck stain. Other lab tests revealed an absolute neutrophil count of 264, a C-reactive protein level of 87, and a negative (1, 3)-beta-D-glucan. A Gram stain of the small amount of fluid from a lesion was negative for organisms or white blood cells with culture and PCRs for varicella zoster virus (VZV) and herpes simplex virus (HSV) pending.

 

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Case Discussion

The biopsy is most consistent with (C) Sweet syndrome, revealing dense neutrophilic infiltration of the dermis without vasculitis, and the absence of clinical and biopsy findings consistent with the other choices. Robert Douglas Sweet, MD, a British dermatologist, first described this rare condition in 1964 in several adults with various infections. It has since been further defined to be categorized into three types:

The manifestations are thought to be a consequence of one or more of the following: hypersensitivity to an antigen (tumor) or dysregulation of cytokines, with some suggestion of genetic susceptibility. The lesions are typically painful papules that may contain a small amount of fluid, plaques and subcutaneous nodules, resembling erythema nodosum (see the column in the February issue of Infectious Diseases in Children). The lesions may appear after or before the diagnosis of a malignancy, but the association is so strong, if they appear without an apparent cause, that a search for an occult malignancy is recommended. The diagnosis is usually suspected clinically, using the historical, physical findings and lab results such as elevated inflammatory markers, and confirmed with biopsy. The management usually includes corticosteroids, which often have a dramatic beneficial effect. Treatment of the underlying disease should go without saying. For a good, brief review, I recommend the UpToDate paper by Joseph F. Merola, MD.

 

In the case presented, the PCRs for HSV and VZV were negative. Varicella zoster may look very atypical in immunocompromised patients with spread to multiple dermatomes, and even without the PCR results, I would still expect to see more typical vesicles (Figure 6). Another hint was the negative Tzanck stain — an oldie, but a goodie.

Lastly, ecthyma gangrenosum is usually a manifestation of bacterial sepsis, most often Pseudomonas aeruginosa, also resulting in necrotic skin lesions. Early ecthyma gangrenosum lesions (Figure 7) may resemble the lesion shown on the patient presented, but within a day or so, it will begin to appear larger and dark with necrosis (Figure 8). Additionally, one might expect the Gram stain of the lesion to reveal the organism.

I would like to thank Austin Smith, MD, from the department of dermatology at Baylor Scott & White in Temple, Texas, for providing pictures and guidance with this case.

• For more information:
• James H. Brien, DO, is with the department of infectious diseases at McLane Children’s Hospital, Baylor Scott & White Health, Texas A&M College of Medicine in Temple, Texas. He also is a member of the Infectious Diseases in Children Editorial Board. Brien can be reached at: jhbrien@aol.com.

Disclosure: Brien reports no relevant financial disclosures.