As an advanced practice nurse, you will examine patients presenting with a variety of disorders. You must, therefore, understand how the body normally functions so that you can identify when it is reacting to changes. Often, when changes occur in body systems, the body reacts with compensatory mechanisms. These compensatory mechanisms, such as adaptive responses, might be signs and symptoms of alterations or underlying disorders. In the clinical setting, you use these responses, along with other patient factors, to lead you to a diagnosis. Consider the following scenarios: Scenario 1: Jennifer is a 2-year-old female who presents with her mother. Mom is concerned because Jennifer has been “running a temperature” for the last 3 days. Mom says that Jennifer is usually healthy and has no significant medical history. She was in her usual state of good health until 3 days ago when she started to get fussy, would not eat her breakfast, and would not sit still for her favorite television cartoon. Since then she has had a fever off and on, anywhere between 101oF and today’s high of 103.2oF. Mom has been giving her ibuprofen, but when the fever went up to 103.2oF today, she felt that she should come in for evaluation. A physical examination reveals a height and weight appropriate 2-year-old female who appears acutely unwell. Her skin is hot and dry. The tympanic membranes are slightly reddened on the periphery, but otherwise normal in appearance. The throat is erythematous with 4+ tonsils and diffuse exudates. Anterior cervical nodes are readily palpable and clearly tender to touch on the left side. The child indicates that her throat hurts “a lot” and it is painful to swallow. Vital signs reveal a temperature of 102.8oF, a pulse of 128 beats per minute, and a respiratory rate of 24 beats per minute. Scenario 2: Jack is a 27-year-old male who presents with redness and irritation of his hands. He reports that he has never had a problem like this before, but about 2 weeks ago he noticed that both his hands seemed to be really red and flaky. He denies any discomfort, stating that sometimes they feel “a little bit hot,” but otherwise they feel fine. He does not understand why they are so red. His wife told him that he might have an allergy and he should get some steroid cream. Jack has no known allergies and no significant medical history except for recurrent ear infections as a child. He denies any traumatic injury or known exposure to irritants. He is a maintenance engineer in a newspaper building and admits that he often works with abrasive solvents and chemicals. Normally he wears protective gloves, but lately they seem to be in short supply so sometimes he does not use them. He has exposed his hands to some of these cleaning fluids, but says that it never hurt and he always washed his hands when he was finished.