Problem: Based on the following information, what are the provisional diagnosis and differential diagnoses? And what medication(s) are appropriate for this patient?
60 years old male. He complained frequent urination at night. His urinary frequency was worsening over the past month, especially at night. It was associated with decreased urinary flow. He wakes at least 4 times per night to pee with difficulty initiating stream (takes about one minute). He is on currently medications (levothyroxine, ferrous sulfate, and pantoprazole) for his hypothyroidism, iron deficiency anaemia and GERD. He had the left knee arthroplasty done 2 years ago. He quitted smoking for 15 years ago. He drinks 3-4 glasses of wine every week, but no more than 1 daily. He does not use any psychoactive drug. He gets his influenza vaccine annually. His COVID vaccination is also up to date. His dad passed away at age 77 due to diabetic complications. Mum passed away at age 36 due to CA breast cancer. He does not have any siblings. He works as a secondary school teacher. He is married but does not have kids. Based on the physical exam, he looks well and no obvious pain behaviours. He is well groomed. His BMI is within normal range. He is alert, aware, and normal emotional range. His abdomen is soft non-tender, bowel sounds in all quadrants, and no CVAT. His is a circumcised male with no urethral trauma or discharge, and his testes are normal. Two weeks ago, he has a kidney ultrasound done with normal kidney and bladder structures. His post-void residual was 10ml. No renal lithiasis was found. His urinalysis was unremarkable. His urine culture result was with no bacteria growth.