Clinical exam skills: Hand signs

In the third part of our series about clinical exam skills, Ian Bickle takes you through typical questions about hand signs

The first aspect of clinical assessment is observation. This often begins before formal examination during the history taking process. Signs identified in the hands may trigger the diagnostic process. Hands offer excellent spot diagnoses in clinical exams of all levels and as talking points for follow up questioning of systemic diseases.

Below are a number of common examples.

Person 1

(1a) Describe the findings on this man's hands.
(1b) Which condition involving the oesophagus is associated with this finding?

Person 2

(2a) Describe the findings on this man's hands.
(2b) How is this finding classified and what are the common causes?

Person 3

(3a) Describe the findings on this woman's hands and arms.
(3b) What are the potential causes?

Answers

(1a) There is a spoon shape to the nails--most evident on both thumbs. This is the clinical sign termed koilonychia. Koilonychia is classically seen in iron deficiency anaemia, however you may see it in thyrotoxicosis. This man was admitted to hospital with shortness of breath on exertion and found to have a haemoglobin concentration of less than 10 g/dl. His serum B-12 and folate were within normal limits. He responded well to oral iron supplementation.

(1b) Iron deficiency anaemia is found in association with an oesophageal web (a thin membranous band arising from oesophageal wall) in Plummer-Vinson (Brown-Patterson-Kelly) syndrome--but it is rare. This condition is associated with the development of squamous cell carcinoma of the oesophagus. It typically occurs in middle aged females.

(2a) There is an increase in the size of the distal aspects of the fingers in conjunction with an increased longitudinal curvature of the nail (the curve of the nail seen from the side is greater than normal). These findings are in keeping with a clinical diagnosis of grade 3 finger clubbing. They are described as "drum stick" in nature. The cause of finger clubbing remains unknown (see box). The man in this example is a 50 year old smoker, with no previous documentation of finger clubbing. This should be considered to be due to malignancy until proven otherwise.

(2b) Finger clubbing can be graded depending on its stage of development.

Stage 1 - The fluctuation of the nail bed, which may be described as sponginess, increases. There may be glossiness to the adjacent skin over the nail bed.

Stage 2 - Curvature of the nail bed increases leading to obliteration of the diamond created by opposing the dorsal surface of the terminal phalanx of identical fingers from either hand (clinically referred to as Scaramoth's sign).

Stage 3 - The longitudinal curvature of the nail increases and the enlarged finger tips are referred to as drum sticks (figs 3 and 4).

Stage 4 - Hypertrophic pulmonary osteoarthropathy is due to subperiosteal reaction and new bone formation which typically affects the wrists and ankles.

(3a) Both hands and over the extensor aspects of the elbows have multiple white nodular areas. A number of the lesions have broken the surface of the skin with white chalky material (urate crystals) discharging. There is erythema in the surrounding skin. This is chronic tophaceous gout. The pinna of the ear is another classical location for a gouty tophus.

(3b) Gout is caused by the deposition of urate crystals within the joints and soft tissues. Although commonly due to hyperuricaemia (high uric acid levels in the blood) it regularly occurs in those with a normal uric acid level. Uric acid is a metabolite of purine. Gout can occur for the following three underlying reasons:

1. Increased purine consumption from high purine containing foods--for example, alcohol, game meats, and sardines.

2. Increased purine production or myeloproliferative lymphoproliferative disease and chemotherapy increase cell turnover and cell lysis increasing the amount of purine. Rare enzymatic conditions such as Lesch-Nyhan syndrome also fall into this catergory.

Decreased uric acid excretion. Diuretics and aspirin are common offenders as is allopurinol which ironically is used as a prophylactic agent in recurrent gout. Starvation and dehydration reduce the ability to excrete uric acid.

Ian Bickle Senior house officer, Department of Medicine, Royal Victoria Hospital, Belfast
Email: clonovara@yahoo.co.uk


studentBMJ 2004;12:393-436 November ISSN 0966-6494