A 35-year-old man presents to a general medical clinic complaining of excruciating pain during and after bowel movements, which he describes as sharp and tearing. He reports that he has been reluctant to pass stool for the past week due to the severity of the pain, leading to increasing constipation. He occasionally observes bright red blood streaks on the toilet paper and sometimes a few drops in the toilet bowl. These symptoms have been intermittently present for about two months, but have become constant and more intense over the last two weeks. He has a history of chronic constipation, often requiring significant straining. He denies fever, chills, or significant weight loss. On examination, his vital signs are stable: temperature is 37.0°C, blood pressure is 125/80 mmHg, heart rate is 70 beats/min, and respiratory rate is 15 breaths/min. Inspection of the perianal area reveals a small, superficial linear ulceration at the posterior midline, immediately distal to the dentate line. The area is exquisitely tender to palpation, precluding a digital rectal examination without significant discomfort. Given this clinical presentation, what is the most appropriate initial diagnosis and subsequent management strategy?

A 32-year-old woman presents to a general medical clinic complaining of severe perianal pain that began approximately 5 days ago and is significantly worsened by bowel movements. She describes sharp, tearing pain during defecation, followed by a throbbing sensation for several hours. She has also noted bright red blood streaking on the toilet paper and occasionally dripping into the toilet bowl. Her diet is notable for a low intake of fruits and vegetables, and she admits to chronic constipation. She denies fever, chills, or significant weight loss. On physical examination, her vital signs are stable: temperature 36.8°C, blood pressure 128/84 mmHg, heart rate 72/min, respiratory rate 16/min, oxygen saturation 99% on room air. Abdominal examination reveals no tenderness or masses. Rectal examination is extremely painful and reveals a linear tear in the posterior midline of the anal canal, extending from the dentate line. There is no evidence of induration, purulent discharge, or large external hemorrhoids. Considering the clinical presentation and physical findings, what is the most likely diagnosis and the appropriate initial therapeutic intervention?

A 5-year-old girl is brought to the primary care clinic by her mother, expressing concern about her daughter's bowel habits. For the past six months, the girl has been passing large, hard stools, often only every 3-5 days, causing significant straining and occasional perianal pain. Her mother also reports frequent episodes of fecal soiling in her underwear. The girl has begun to resist toilet use, preferring to hide when she feels the urge to defecate. She had a normal birth history, born at term with a weight of 3.4 kg, had no meconium delay, and was exclusively breastfed for the first six months. Her diet consists primarily of processed foods, and she drinks limited water. On physical examination, she appears well-nourished. Abdominal examination reveals a soft, non-distended abdomen with palpable stool in the left lower quadrant. A perianal inspection shows a small, healing linear fissure at the posterior midline. What is the most appropriate initial diagnostic assessment and subsequent therapeutic intervention?