Isolated Cutaneous Crohn's Disease of the Vulva and Gluteal Region With Coexisting Hidradenitis Suppurativa

Crohn's disease (CD) is a chronic inflammatory disorder with extraintestinal involvement in up to 40% of patients, most often affecting the skin [1]. Cutaneous manifestations are categorized as: (i) direct extension from the gastrointestinal tract, (ii) reactive dermatoses such as erythema nodosum, (iii) nutritional deficiency–related dermatoses, and (iv) specific granulomatous lesions at non-contiguous sites, termed metastatic cutaneous Crohn's disease (CCD/MCD) [2]. Vulvar CCD is rare, reported in < 0.25% of women with CD [1]. Global reviews have compiled just over 250 cases across age groups and sites, while Indian data are limited to sporadic case reports [3]. Notably, up to one-third of CCD cases occur in the absence of gastrointestinal involvement, often preceding or existing independently of bowel disease [4]. Clinical features include persistent labial swelling, deep fissures or ulcers, and hypertrophic plaques [4, 5]. Shared pathogenic pathways between CCD and HS, including dysregulation of TNF-α and the IL-23/Th17 axis, may explain occasional coexistence [6]. A 34-year-old woman from south India presented with recurrent painful vulvar swellings and ulcers for 6 years, axillary nodules with purulent discharge present for 4 years, intermittent oral aphthae for 2 years, and recent linear ulcers in the gluteal cleft. She reported pain on defecation, dyspareunia and no gastrointestinal, articular, or ocular symptoms. On examination, there was diffuse, firm edema with infiltration of the labia majora with multiple deep nodules over the mons pubis and perineum (Figure 1A). The gluteal cleft had three deep linear “knife cut” ulcers (Figure 1B). Both axillae showed hidradenitis suppurativa lesions with draining sinuses and fibrotic bridging scars (Hurley stage II) (Figure 2A). Oral examination showed aphthae with gingival hypertrophy. Perineal ultrasonography demonstrated lobulated thickening of pubic and vulvar skin with multiple intercommunicating tracts and small abscesses, along with bilateral femoral lymphadenopathy. Vulvar skin biopsy showed epidermal hyperplasia with irregular acanthosis, well-defined non-caseating granulomas and mid-dermal lymphohistiocytic infiltrate. These granulomas contained epithelioid histiocytes with Langhans and foreign-body giant cells, surrounded by a lymphocytic cuff and focal perivascular inflammation (Figure 2B). No necrosis or vasculitis was noted, and special stains (acid-fast bacillus [AFB], periodic acid-Schiff [PAS], Grocott's methenamine silver [GMS]) were negative. Colonoscopy and multiple biopsies from the terminal ileum, caecum, colon, and rectum were normal. A diagnosis of isolated vulvar and gluteal cutaneous Crohn's disease (CCD) with coexisting hidradenitis suppurativa (Hurley II) was made. Treatment given was tablet doxycycline, intralesional triamcinolone acetonide to vulvar plaques (3–4 weeks apart), and methotrexate 7.5 mg weekly (which was discontinued due to gastric intolerance). The patient reported moderate improvement, reduced pain, softening of vulvar nodules, and no new lesions at follow-up. This case illustrates cutaneous Crohn's disease at genital and gluteal sites with no gastrointestinal involvement, a pattern reported in up to one-third of cases [2, 3]. The presence of chronic vulvar edema, deep linear knife-cut ulcers, and coexisting hidradenitis suppurativa is consistent with the described morphology of vulvar Crohn's disease [4, 5]. The coexistence of hidradenitis suppurativa with vulvar cutaneous Crohn's disease is clinically important. Studies have investigated an association between Crohn's disease and hidradenitis suppurativa. This association supports the hypothesis that a similar pathogenic mechanism contributes to both diseases, providing new possibilities for functional studies and therapy development. Vulvar Crohn's disease should be considered in chronic vulvar edema when characteristic “knife-cut” ulcers are seen with deep nodules and abscesses. Co-occurrence of hidradenitis suppurativa is rarely seen and biopsy helps to clinch the diagnosis. The authors declare no conflicts of interest. The data that support the findings of this study are available on request from the corresponding author. The data are not publicly available due to privacy or ethical restrictions.