A 27-year-old Ghanaian woman presents in the emergency department with a three-day history of headache, nausea, and vague lower abdominal pain. She has no significant past medical history, but is eight-weeks pregnant with her first child. She lives in London and returned from a trip to Ghana two weeks ago. You have been assigned her initial assessment... 100 Cases in Clinical Pathology presents 100 clinical scenarios commonly seen by medical students and junior doctors in the emergency department, outpatient clinic, or in general practice in which an understanding of the underlying clinical pathology is central to arriving at the correct diagnosis. A succinct summary of the patient's history, examination, and initial investigations—histopathology, chemical pathology, haematology, microbiology, and clinical immunology as appropriate—is followed by questions on each case, with particular emphasis on the interpretation of the results and the arrival at a clinicopathologic diagnosis. The answer includes a detailed discussion on each topic, providing an essential revision aid as well as a practical guide for students and junior doctors. Making speedy and appropriate clinical decisions, and choosing the best course of action to take as a result, is one of the most important and challenging parts of training to become a doctor. These true-to-life cases will teach students and junior doctors to recognize important clinical conditions, to request the appropriate pathological investigation and correctly interpret those results, and, as a result, to develop their diagnostic and management skills.