Atypical Mycobacterial Infection Mimicking Psoriasis in an Elderly Patient: Diagnostic Challenges and Management.

Atypical mycobacterial infections can have diverse clinical presentations, frequently resulting in diagnostic challenges. This study examines an uncommon atypical mycobacterial disease in an older patient, initially misidentified as psoriasis, emphasizing the difficulties in diagnosing and managing the condition. A 70-year-old male patient arrived at the dermatology department at National Hospital and Medical Centre, Lahore, with a persistent, dry, red rash mainly affecting his arms and legs. The patient had a medical background of diabetes mellitus and hypertension. Initial clinical diagnosis suggested psoriasis based on the appearance and patient's age. The patient was started on conventional psoriatic therapies. However, there was only a slight improvement, which led to the need for additional inquiry. Skin biopsies were conducted, uncovering the presence of granulomatous inflammation. Following cultures and polymerase chain reaction (PCR) tests, the presence of atypical mycobacteria was established. Subsequent laboratory tests eliminated the possibility of tuberculosis (TB) and other prevalent diseases. The conclusive diagnosis was an unusual mycobacterial infection, which posed a challenge due to its clinical similarity to psoriasis. The patient was treated with antibiotics appropriate to the mycobacterial species discovered. The duration of the treatment spanned six months, resulting in a notable amelioration of the skin lesions. The patient is being closely observed for any potential reoccurrence. This case highlights the significance of including atypical mycobacterial infection as a possible diagnosis for persistent dermatological problems, particularly in persons with impaired immune systems. It emphasizes the need for biopsy and culture in unusual situations of suspected psoriasis. This instance also demonstrates the intricacies associated with managing older patients with multiple concurrent medical issues. Unusual mycobacterial infections can imitate conventional skin disorders such as psoriasis, presenting considerable difficulties in diagnosis. Having a strong suspicion and doing relevant laboratory tests are essential for achieving an accurate diagnosis and efficient treatment.