**Question:** Not true about Malignant otitis externa

A. Malignant otitis externa is a rare infectious condition affecting the outer ear canal and temporal bone
B. It is not associated with diabetes mellitus
C. It is caused by a fungal infection, mainly Aspergillus species
D. It typically presents with severe ear pain and hearing loss

**Correct Answer:** B. Malignant otitis externa is not associated with diabetes mellitus

**Core Concept:** Malignant otitis externa is a severe, progressive, and potentially life-threatening infection of the outer ear canal and temporal bone. It is usually caused by Aspergillus species, particularly Aspergillus niger and Aspergillus fumigatus. The infection progresses rapidly, often leading to skull base involvement and intracranial extension.

**Why the Correct Answer is Right:** Malignant otitis externa is primarily a result of fungal invasion, particularly Aspergillus species. While diabetes mellitus can weaken the immune system, making individuals more susceptible to infections, including malignant otitis externa, it is not the sole risk factor for this condition. Other risk factors include old age, immunosuppressive therapy, and corticosteroid use. Therefore, the statement that malignant otitis externa is exclusively associated with diabetes mellitus is incorrect.

**Why Each Wrong Option is Inaccurate:**

A. While malignant otitis externa does involve the outer ear canal and temporal bone, it is not a rare infection. The condition is relatively common in immunocompromised patients, as mentioned above.

C. Fungal infections are indeed the primary cause of malignant otitis externa, but it is not exclusively caused by fungi. Bacterial infections, particularly Pseudomonas aeruginosa, can also contribute to malignant otitis externa, particularly in immunocompromised patients.

D. Malignant otitis externa typically presents with severe ear pain, but it is not solely characterized by hearing loss. Other symptoms include ear discharge, swelling, and proptosis.

**Clinical Pearl:** In cases of patients with risk factors for malignant otitis externa, a high index of suspicion is crucial for early diagnosis and treatment. Prompt management is essential as the disease can rapidly progress to skull base involvement or intracranial extension, leading to severe neurological deficits and potential mortality.