Which of the following is not directly related to diabetes mellitus?

Diabetes mellitus is predominantly characterized by elevated blood sugar levels, often resulting from issues with insulin production or action. The condition can lead to both systemic and specific symptoms.

Polyuria refers to excessive urination, a common symptom in diabetes due to the kidneys attempting to excrete excess glucose from the bloodstream. Thirst, or polydipsia, is another key symptom linked to diabetes, as high blood sugar levels can induce dehydration, leading to increased thirst.

In contrast, inflammation of the conjunctiva, known as conjunctivitis, is not directly related to diabetes mellitus. While individuals with diabetes can have various eye conditions, such as diabetic retinopathy, conjunctivitis itself is typically caused by infections, allergens, or irritants, and is not a direct complication or symptom arising from diabetes. Therefore, this choice does not align with the defining characteristics or associated symptoms of diabetes mellitus.