Diagnosis: Lupus vulgaris (cutaneous tuberculosis)
A 45-year-old female presented with a slowly enlarging, painless lesion on her right cheek, described as an apple-jelly nodule. The lesion had been present for several months, with no history of trauma or other skin conditions. Upon examination, the characteristic features of the lesion suggested a diagnosis of cutaneous tuberculosis.
A 45-year-old female presented with a painless, slowly enlarging lesion on her right cheek that had been present for approximately six months. The patient noted that the lesion was initially small but gradually increased in size and changed in color. On examination, the lesion was firm, well-defined, and exhibited a characteristic apple-jelly appearance upon diascopy.Location: Right cheek.Size: Approximately 2 cm in diameter.Color: Reddish-brown with a translucent quality.Texture: Firm and elevated.Surrounding skin: Normal, without signs of inflammation.
The lesion began insidiously, with no identifiable triggers or preceding skin conditions. The patient had no significant past medical history and denied any recent travel or exposure to individuals with known tuberculosis. She reported no prior treatments for the lesion, and her family history was unremarkable for dermatological or infectious diseases.Onset: Lesion present for six months.Prior treatments: None attempted.Travel history: No recent travel or exposure to high-risk areas.Social history: Non-smoker, no known exposure to tuberculosis.Family history: No history of tuberculosis or other mycobacterial infections.
Acute / First-Line ManagementRifampicin: 10 mg/kg/day (max 600 mg) for 6-12 months.Isoniazid: 5 mg/kg/day (max 300 mg) for 6-12 months.Pyrazinamide: 25 mg/kg/day (max 2000 mg) for the first two months.Ethambutol: 15 mg/kg/day (max 1600 mg) for the first two months.Workup and Diagnostic ConfirmationSkin biopsy: Histopathological examination revealing caseating granulomas.Acid-fast bacilli (AFB) staining: May help identify mycobacterial infection.Quantiferon Gold test: To assess for latent tuberculosis infection.Cultures: Mycobacterial culture for definitive diagnosis.Long-Term ManagementMonitoring: Regular follow-up every 3-6 months to assess treatment response and side effects.Adherence: Emphasize the importance of completing the full course of therapy.Supportive care: Management of any adverse drug reactions.Referral: Consider referral to a specialist in infectious diseases if complications arise.
Basal cell carcinoma: Typically presents as a pearly papule with telangiectasia; lacks the apple-jelly appearance on diascopy.Granuloma annulare: Presents as annular plaques, often in children; lacks the firm, raised, apple-jelly characteristic.Leprosy: Often presents with skin lesions and neurological symptoms; requires specific travel history or exposure to endemic areas.Cutaneous leishmaniasis: Typically presents with ulcerative lesions and history of travel to endemic regions.Dermatofibroma: Firm lesions with a dimple sign; lacks the color and appearance of apple-jelly.Cutaneous sarcoidosis: May present with plaques and nodules but differs in systemic involvement and histopathological features.Psoriasis: Presents with well-defined plaques and silvery scales; does not exhibit the apple-jelly appearance.Chronic eczema: Typically presents with pruritus and inflammation; lacks the specific nodular form.
High-Yield PearlsApple-jelly: The classic descriptor for the appearance of lupus vulgaris lesions upon diascopy, indicative of the underlying pathology.Diagnosis: Definitive diagnosis relies on histopathological findings revealing caseating granulomas.First-line therapy: Combination therapy with rifampicin, isoniazid, pyrazinamide, and ethambutol is effective in treating cutaneous tuberculosis.Monitoring: Regular follow-up is crucial for assessing treatment efficacy and managing potential side effects.Public health: Awareness of tuberculosis risk factors is essential for early detection and management of cutaneous manifestations.A thorough understanding of the clinical features and appropriate management of cutaneous tuberculosis ensures timely diagnosis and effective treatment, preventing progression and complications.
Tags: lupus vulgaris, cutaneous TB