An Approach to Unintentional Weight Loss

Introduction
Evaluation Priorities

Context: OPD

Introduction
Unintentional weight loss is quite common, and patients and their family will often seek medical opinions about the cause. The key concern for most is the possibility that an occult malignancy is responsible for this condition.

Different terms are used in textbooks and the literature, although clinicians often use them interchangeably.

Unintentional weight loss = weight loss > 5% body weight, over 6 months or more
Cachexia = weight loss due to MUSCLE loss
Sarcopenia = syndrome characterized by loss of muscle mass, strength, and performance

In reality, progressive weight loss is primarily a clinical marker of frailty; it is very common in patients over the age of 65 and is seldom caused by a single curable condition, however it almost always warrants investigation.

In at least 30% of patients, no diagnosis is ever reached. Similarly, in a country where extreme poverty is common, malnutrition (inadequate access to food), inextricably woven with HIV and recurrent TB, is an extremely common cause of weight loss.

There are many potential causes, and most are unrelated to surgery. The role of the surgeon in this context is to be aware of the broad picture and to guide the diagnostics in cases that may relate to gastrointestinal pathology, or when tissue diagnosis require invasive interventions.

A truly occult cancer is an uncommon cause of cachexia, in the absence of other overt symptoms or signs.

Given the broad differential diagnosis, there is no one-size-fits-all approach, and as always a thorough
clinical review is essential to guide further management and investigations.

This is where the doctor should go back to the basics of clinical methods: and take a comprehensive history, systematic enquiry, followed by a full physical examination, keeping in mind the common causes mentioned above. It is absolutely vital that the patient is weighed at the first and subsequent appointments. Sustained and documented weight loss is a worrying symptom which will almost always need special investigations. It is unusual that one will be able to reassure the patient that the weight loss is not serious without fully investigating the patient.

Evaluation Priorities

What is the diagnosis?

In the absence of an overt clinical diagnosis, it is reasonable to do a broad range of investigations to identify the commonest causes.

Further investigations will be driven by any abnormality picked up in the above panel of tests.

Should they all be COMPLETELY NORMAL, and patients is without any clear symptoms to guide you, it is reasonable to hold off further tests, and review the case in 6-8 weeks time.

I am not quite sure what is going on, and I need more information

Be selective in the investigations, and use common sense instead.

The investigations below are occasionally helpful.