Acute generalized pustular bacterid.

The case of a 70-year-old Japanese man with acute generalized pustular bacterid.

A 70‐year‐old Japanese man, who had antecedent symptoms of upper respiratory tract infection, presented with acute onset of pustules on the hands and feet. Physical examination revealed multiple pustules with a red halo not only on the palms and soles, but also on the dorsal surface of the hands and feet (Figure 1), which spread to the forearms and lower extremities. The patient had a fever of approximately 40.0°C. Total leukocyte count, neutrophil count, and C‐reactive protein (CRP) level were elevated (11 300/μL, 7480/μL, and 4.82 mg/dL, respectively). Histopathological findings showed intraepidermal pustules and neutrophil infiltrates within and around the vessels with erythrocyte extravasation (Figure 2). Skin cultures from affected lesions for microorganism were negative. The patient had no personal or family history of psoriasis. A definitive diagnosis of acute generalized pustular bacterid (AGPB) was made.1 The patient was treated with 750 mg/d of cefaclor, which improved skin lesions rapidly. After the 7 day treatment, skin lesions resolved and the fever and sore throat were also relieved. The patient is doing well without recurrence of the lesion.

Figure 1

A, Multiple pustules on the extremities of a 70‐year‐old Japanese man. B, Pustules with a red halo on the extremities

Figure 2

Histopathology, showing intraepidermal pustules and neutrophil infiltrates within and around the vessels with erythrocyte extravasation (hematoxylin and eosin staining)

Acute generalized pustular bacterid was first described by Andrews et al2 and the concept was supported by Tan.1 AGPB is characterized by sterile pustules with a red halo but not scaly erythema on the trunk and extremities accompanied with intermittent fever up. The disease process seems to be induced by upper respiratory infection, especially streptococcal infection.3 Therefore, anti‐streptolysin O (ASO) titer is often elevated at the onset of the disease, although ASO titer was not elevated in our case and streptococcal infection was not confirmed with a throat culture. The differential diagnosis includes palmoplantar pustulosis (PPP) and generalized pustular psoriasis (GPP). It is possible to differentiate AGPB by typical clinical manifestations as follows: coincidence with an infection, no personal or family history of psoriasis, isolated sterile pustules and no lesions of psoriasis vulgaris, good response to antibiotics, and a short course.4 Additionally, the typical pustules in AGPB are observed on the palms, soles, and the dorsal surface of the hands and feet, while those in PPP are on the palm or sole, but not on the dorsal surface of the hand or foot. The definitive diagnosis of AGPB is confirmed by histopathological findings. Leukocytoclastic vasculitis is observed in AGPB but not PPP. In our case, histopathological findings showed neutrophil infiltrates within and around the vessels with erythrocyte extravasation, although vascular damage was slight and fibrinoid degeneration was not observed within the biopsied specimen. In addition, spongiform pustule, which is observed as multiple neutrophils infiltrate into the upper suprabasal cell layer forming spongiosis, is highly diagnostic for GPP. Clinicians should consider this diagnosis in patients who present with these clinical manifestations. Although there is a controversy as to whether AGPB is a separate disease or a variant of GPP or PPP, AGPB should be regarded as a separate disease of pustular dermatosis and further case accumulation will contribute to the better understanding of the disease.

CONFLICT OF INTEREST

The authors have stated explicitly that there are no conflicts of interest in connection with this article.