Bacillary Angiomatosis in an Immunocompetent Individual

Sir,

A 45-year-old female presented with tender erythematous papulonodular eruptions on arm, forearm, and ankle since past 1 month [Figure 1a and b].

Figure 1.

(a) Multiple hyperpigmented nodules present over forearm and fingers ranging from 0.5 cm to 1.5 cm in size. (b) A single well-defined nodule on lateral malleolus. (c) Evidence of early response to therapy on day 10 after starting therapy. (d) Residual pigmentation with flattening of lesion at end of 4 months of therapy

The patient had no history of any systemic illness and there was no mucous membrane involvement, no lymphadenopathy, or hepatosplenomegaly. No pathological and radiological abnormality was detected. Both venereal disease research laboratory (VDRL) test and enzyme-linked immunosorbent assay (ELISA) test for HIV were negative.

The clinical differential diagnosis of pyogenic granuloma, verruca perunana, Kaposi's sarcoma, lymphocytoma cutis, and lupus vulgaris was considered.

A diagnostic skin biopsy was done which showed prominent angiomatosis [Figure 2a] along with prominent leukocytoclasia on the background of ectatic blood vessels [Figure 2b] which showed CD31 positivity thus confirming angiogenesis [Figure 2c]. The endothelium of the blood vessels appear plump and the RBC's are surrounded by neutrophils. Identification of the causative bacillus by Warthin-Starry method was not done due to lack of laboratory facilities; however, special staining with Grocott-Gomorimethenamine silver stain was done which showed multiple clumps of argyrophilic bacteria [Figure 2d]. At this stage history of cat scratch was again asked and patient definitely recalled a strong positive history of nail scratch from a domestic cat.

Figure 2.

(a) (H and E 40×) Evidence of prominent angiogenesis. (b) (H and E ×40) Prominent leukocytoclasia is visible on the background of numerous ectatic blood vessels. (c) Immunohistochemistry staining (CD31) positive indicating vascular angiogenesis. (d) Special staining with Grocott-Gomorimethenamine silver stain showed numerous clumps of argyrophilic bacteria scattered throughout the biopsy specimen

The final diagnosis of bacillary angiomatosis (BA) was made which was supported by special stain and immunohistochemistry studies.

The patient was started on oral doxycycline 100 mg twice daily and showed good response to therapy which was evident by regression of lesions with residual pigmentation within 4 months of starting therapy [Figure 1c and d]. The patient is under regular follow-up without any evidence of reoccurrence.

BA is an infectious proliferative vascular disease and its association with HIV was first described by Stoler et al.[1] in the year 1983. Bartonellaquintana and Bartonellahenselae organisms are associated with BA.[2] Bartonella is the only genus of bacteria that is capable of producing cutaneous angioproliferation as is evident from clinical presentation in cases of verruca perunana and BA.[3] The incubation period ranges from 10 days to 210 days with average being 60 days. Skin is the most commonly affected site with occurrence ranging from 55% to 90% of cases.[4] Most of the reported cases are from immnuocompromised hosts with few reports of its occurrence in immunocompetent host. Our patient was not immunocompromised as there was no history of any repeated infections, usage of immunosuppressive drugs, or no findings suggestive of any underlying chronic infection or malignancy and was seronegative for HIV test. It is now well-documented that human infections occur either by direct contact with cats or has a history of recent licking, scratching, or biting by a cat, it can also spread by an arthropod vector.[2] In this present case, patient definitely recalled a strong positive history of contact with domestic cat before the onset of her lesions (recent scratching).

This case is reported for its rarity with an objective to increase awareness and consider BA in immunocompetent individuals also and not just in seropositive patients alone. Diagnosis if made early results in resolution of lesions; however, a prolonged course of therapy is usually required in most of the cases.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that name and initial will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

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Conflicts of interest

There are no conflicts of interest.