It is unlikely that you would get someone who is severely clinically malnourished in the exam but certain degrees of protein-calorie malnutrition in the long case inpatient would be a reasonable occurrence. At least 25% of acute care inpatients apparently show signs of protein-calorie malnutrition which is a pathologic depletion of the body’s lean tissues caused by starvation +/- catabolic stress.
Historical signs that would point to a diagnosis of PEM include unremitting, involuntary weight loss that is greater than 10% in the previous 6 months, and especially in the last few weeks; severely curtailed food intake; persistent, essentially daily gastrointestinal symptoms such as anorexia, nausea, vomiting or diarrhoea over the last 2 weeks; marked reduction in physical capacity and the presence of metabolic stress due to trauma, inflammation or infection.
Clinical signs include a reduced body weight, muscle wasting and decreased strength, reduced respiratory and cardiac muscle capacity, skin thinning, hypothermia, apathy, oedema, immunodeficiency. Perhaps look for a loss of subcutaneous fat and decreased mass in the temporal, deltoid, intercostal, upper arm, gluteal, thigh and calf muscles. When commenting on its possibly in an inpatient be sure also to mention more profound measures of malnutrition such as cheilitis and glossitis (Vit B) and ask for nutritional indices such as folate, B12, Iron levels, Albumin and pre-albumin.