What is the target?BMJ 2009; 338 doi: https://doi.org/10.1136/bmj.b1604 (Published 27 May 2009) Cite this as: BMJ 2009;338:b1604
- M Lemyze, specialist registrar in critical care medicine1,
- S Salomon, specialist registrar in critical care medicine1,
- D Brown, specialist registrar in emergency medicine2,
- P Detouche, specialist registrar in critical care medicine1,
- F Collet, specialist registrar in critical care medicine1
- 1Department of Critical Care Medicine, Broussais Hospital, Saint Malo, France
- 2Department of Emergency Medicine, Broussais Hospital, Saint Malo, France
- Correspondence to: M Lemyze, Department of Critical Care Medicine, Broussais Hospital, 35400 Saint Malo, France
A 44 year old man was brought to the emergency department with a two day history of fever, skin rash, and a rapidly progressive shortness of breath. On examination, notable observations included an extensive rash, cyanosis, a fast respiratory rate (40 breaths/min), bilateral crackles on lung auscultation, and a temperature that reached a maximum of 40.4°C. Arterial blood gas levels showed severe hypoxemia (PaO2, 48 mmHg; fraction of inspired oxygen [FiO2], 21%). Chest radiography showed bilateral consolidation of the air spaces, mainly in the lower lung fields, which confirmed the clinically suspected diagnosis of community acquired pneumonia (fig 1).⇓
1 What is the clinical diagnosis for the patient’s skin rash?
2 What is the most likely cause for his community acquired pneumonia?
3 How should the diagnosis be confirmed?
4 How should this patient be managed?
1 This patient has erythema multiforme, which is characterised by a maculopapular rash made of multiple round “bull’s eye” target shaped lesions.
2 Mycoplasma pneumoniae is the infectious agent most likely to be responsible for both extensive community acquired pneumonia and erythema multiforme.
3 The key to diagnosis is serological testing.
4 Severe community acquired pneumonia that results in acute respiratory failure with persisting deep hypoxaemia should be managed in an intensive care unit. Treatment should entail early intravenous administration of an empirical antibiotic regimen comprising broad spectrum β-lactam and a macrolide.
1 Diagnosis of the skin rash
The term “erythema multiforme” is used to describe a special category of maculopapular rash that encompasses a wide range of different morphologic types (including plaques, vesicles, and bullae), which can occur concurrently. Rashes of this nature occur as a reaction to an infection or to medication (box 1);1 …