Case history

A 76 year old woman presented at the accident and emergency department with increasing shortness of breath and fatigue for the past few weeks. Nevertheless, she continued to smoke. She reported that her clothes had become loose recently. On examination the left side of her chest was dull to percussion and she had reduced breath sounds on that side.

Questions

1. What is the diagnosis?
2. Describe the chest radiograph and what are the other causes of the abnormality?
3. What would you expect to find on clinical examination in a patient with this condition?

Answers

1. Bronchogenic carcinoma
2. The chest radiograph shows a left sided pleural effusion. Note the meniscus (curvature) at the top of the shadowing which is suggestive of fluid.

   Causes of a pleural effusion can be broadly divided into transudates and exudates. As a general rule exudates have a protein concentration greater than 30g/l. More accurate determination may be achieved using Light's criteria, which compare pleural protein and lactate dehydrogenase to levels in the blood. Cholesterol is also lower in transudates.

   Transudates are often bilateral although if unilateral they tend to affect the right side. Causes include cardiac failure (although effusions in chronic failure can have an exudate), nephrotic syndrome, and liver failure. Hypothyroidism, Meig's syndrome, and yellow nail syndrome are also recognised but rarer causes.

   Exudates may be caused by infections, including tuberculosis, neoplastic disease (primary or metastatic carcinoma, lymphoma, mesothelioma), pulmonary embolic disease, rheumatoid arthritis, pancreatitis, and others.

3. A patient with carcinoma of the lung may look unwell, cachectic, and breathless, perhaps requiring supplemental oxygen. There may be a pot next to the patient with bloodstained sputum. On examination of their hands, tar staining from cigarettes is often noted. Adenocarcinoma however is not linked to smoking. Clubbing of the fingernails may be seen. In aggressive carcinomas clubbing may not have enough time to develop. Muscle wasting may be noted if the lesion invades the brachial plexus. The patient may be tachycardic if anaemic and atrial fibrillation (AF) may result from invasion of the heart by the tumour but do not forget the commoner causes of AF. Carbon dioxide retention may be related to underlying chronic obstructive pulmonary disease. This manifests with a bounding pulse and coarse flapping tremor of the hands.

   On examination of their respiratory system tachypnoea, cyanosis, and tracheal deviation may be present. A mass in the chest may be heard as a polyphonic wheeze. A pleural effusion will be demonstrated by reduced expansion, a stony dull percussion note, and reduced breath sounds on the affected side. Bronchial breathing may be heard at the top of the fluid.

   Abnormal neurological signs include a Horner's syndrome (often seen in exams), peripheral neuropathy, and rarely cerebellar and Eaton-Lambert syndromes. A hoarse voice results from damage to the recurrent laryngeal nerve. A raised hemidiaphragm results from a phrenic nerve palsy. Skin signs include dermatomyositis, acanthosis nigricans, and, very rarely, erythema gyratum repens.