Type 2 Diabetes Mellitus: This is the most likely diagnosis due to the increasing prevalence of type 2 diabetes in young adults, often associated with obesity, physical inactivity, and an unhealthy diet. The patient's age and the presence of increased random blood glucose levels make this a probable diagnosis.

Type 1 Diabetes Mellitus: Although less common than type 2, type 1 diabetes can occur at any age and is characterized by an absolute deficiency of insulin production. Symptoms such as polyuria, polydipsia, and weight loss, along with elevated blood glucose, would support this diagnosis.
Gestational Diabetes: If the patient is female and pregnant, gestational diabetes should be considered. It typically develops during the second or third trimester and is associated with insulin resistance and impaired insulin secretion.
Steroid-Induced Hyperglycemia: The use of corticosteroids can lead to increased blood glucose levels due to their effect on glucose metabolism. This is a consideration if the patient is on steroid therapy for any reason.
Polycystic Ovary Syndrome (PCOS): PCOS is associated with insulin resistance, which can lead to elevated blood glucose levels. Other symptoms such as irregular menstrual cycles, hirsutism, and obesity may also be present.

Diabetic Ketoacidosis (DKA): A life-threatening complication of diabetes that can occur in both type 1 and type 2 diabetes, characterized by hyperglycemia, metabolic acidosis, and ketosis. Early recognition and treatment are crucial.
Hyperosmolar Hyperglycemic State (HHS): Another serious complication, more common in type 2 diabetes, characterized by extreme hyperglycemia, dehydration, and altered mental status. Prompt diagnosis and management are essential to prevent mortality.
Pituitary or Adrenal Tumors: Rarely, tumors of the pituitary or adrenal glands can cause hyperglycemia due to excessive production of hormones like cortisol (Cushing's syndrome) or growth hormone (acromegaly). These conditions require specific treatment and can have significant morbidity if not addressed.

MODY (Maturity-Onset Diabetes of the Young): A form of diabetes caused by genetic mutations that affect insulin production. It typically presents at a young age and can be mistaken for type 1 or type 2 diabetes but has distinct genetic and clinical features.
Lipoatrophic Diabetes: A rare condition characterized by the loss of body fat, leading to insulin resistance and diabetes. It can be congenital or acquired.
Wolfram Syndrome: A rare genetic disorder also known as DIDMOAD (Diabetes Insipidus, Diabetes Mellitus, Optic Atrophy, and Deafness), which includes diabetes as one of its manifestations.