Examine this patient's chest.
· Abrupt onset of symptoms.
· Cough with purulent sputum.
· Fever with sweating or rigors.
· Pleuritic chest pain (pp 251,256).
· Shortness of breath.
· Nausea, vomiting, diarrhoea (consider Legionella).
· Mental status changes (esp. elderly).
· Purulent sputum (if bacterial in aetiology).
· Reduced movement of the affected side.
· Trachea central.
· Impaired percussion note.
· Bronchial breath sounds.
This patient has left lower lobe consolidation with purulent sputum (lesion) indicating a bacterial pneumonia (aetiology).
Read N Engl J Med 1995; 333:1618 24; Br J Hasp Med 1993; 49: 346-50.
What is the aetiology?
· Bacterial pneumonia.
· Bronchogenic carcinoma.
· Pulmonary infarct.
How would you investigate suspected bacterial pneumonia ?
· Full blood count, serum urea, electrolytes and liver function tests.
· Sputum and blood cultures.
· Arterial blood gases.
· Test for Legionella (culture, direct fluorescent-antibody test, or urinary antigen assay), mycoplasma immunoglobulin M.
· Consider serological testing for human immunodeficiency virus (for patients 15-54 years old, particularly when there is
lymphopenia or a low CD4 cell count).
What are the causes of a poorly resolving or recurrent pneumonia ?
· Carcinoma of the lung.
· Aspiration of a foreign body.
· Inappropriate antibiotic.
· Sequestration (rare; suspect if left lower lobe is involved).
What do you know about atypical pneumonias?
Typical pneumonia is caused by pneumococcus (Streptococcus pneumoniae), whereas atypical pneumonia is that not due to
pneumococcus; the latter may be caused by Mycoplasma, Legionel/a, Chlamydia, Coxiella, etc. The clinical picture in atypical
pneumonia is dominated by constitutional symptoms, such as fever and headache, rather than respiratory symptoms.
What do you know about mycoplasma pneumonia?
Mycoplasma pneumoniae is an important cause of atypical pneumonia, it is an important community-acquired pneumonia and
epidemics are seen every 4 years or so. Its incubation is 2-3 weeks and it is usually seen in children and young adults. Reinfection
can occur in older patients with detectable M. pneumoniae antibody. Like all other pneumonias, mycoplasma pneumonia is common
in winter months.
What are the extrapulmonary manifestations of mycoplasma pneumonia?
· Arthralgia and arthritis.
· Autoimmune haemolytic anaemia.
· Neurological manifestations involving both central and peripheral nervous systems. · Pericarditis, myocarditis.
· Hepatitis, glomerulonephritis.
· Non-specific rash, erythema multiforme and Stevens-Johnson syndrome.
· Disseminated intravascular coagulation (DIC).
What are the complications of pneumonia?
· Lung abscess.
· Adult respiratory distress syndrome.
· Multiorgan failure, renal failure.
· Haemolytic syndrome.
Which antibiotics would you use in a patient with community-acquired pneumonia where the pathogen is not known?
The British Thoracic Society recommends that empirical therapy 'should always cover' Strep. pneumoniae. The preferred regimen is
amoxicillin or penicillin; when
Legionella or M. pneumoniae is specifically suspected, erythromycin should be gwen, and antibiotics directed against
Staphylococcus aureus should be considered during epidemics of influenza.
What are the poor prognostic factors in patients with community-acquired pneumonia ? · Age over 65 years.
· Coexisting conditions such as cardiac failure, renal failure, chronic obstructive pulmonary disease, malignancy.
· Clinical features: respiratory rate >30 per min, hypotension (systolic blood pressure <90 mmHg or diastolic pressure <60
mmHg), temperature >38.3°C, impaired mental status (stupor, lethargy, disorientation or coma), extrapulmonary infection (e.g.
septic arthritis, meningitis).
· Investigations: haematocrit <30%, white cell count 30 000 per mm3, azotaemia, arterial blood gas <60 mmHg while
breathing room air, chest radio-graph showing multiple lobe involvement, rapid spread or pleural effusion.
· Microbial pathogens: Staph. aureus, Legionella, Strep. pneumoniae.
What do you know about pulmonary eosinophilic disorders?
Crofton et al described five classes of pulmonary eosinophilic disorder (Thorax 1952; 7: 1-35):
· L6ffler's syndrome: characterized by transient pulmonary infiltrates and peri-pheral eosinophilia. It is associated with parasitic
infections, drug allergies and exposure to inorganic chemicals such as nickel carbonyl. The course is benign and respiratory
failure almost unknown.
· Eosinophilia in asthmatics: the most common cause is allergic broncho-pulmonary aspergillosis. This condition is benign but
· Tropical eosinophilia which is secondary to filarial infection (Wuchereria bancrofti or W. malayi Brug).
· Churg Strauss syndrome. Diagnosis requires four of the following features: asthma; eosinophilia greater than 10%;
mononeuropathy or polyneuropathy; paranasal sinus abnormality; non-fixed pulmonary infiltrates visible on chest radiographs;
blood vessels with extravascular eosinophils found on biopsy.
· Chronic eosinophilic pneumonia: chronic debilitating illness characterized by malaise, fever, weight loss and dyspnoea. The
chest radiograph shows a peri-pheral alveolar filling infiltrate predominantly in the upper lobes (the 'photo-graphic negative' of
What do you know about broncbopulmonary sequestration?
It is an uncommon congenital lesion in which a portion of non-functioning lung tissue is detached from the normal lung and supplied
by an anomalous systemic artery, usually arising from the aorta or one of its branches. The tissue has no communication with the
bronchopulmonary tree. Two types of sequestration have been described: extralobar and intralobar. An extralobar sequestration has
its own pleural lining, which separates it from the remaining lung tissue, and the intralobar type shares its pleura with the adjacent
normal lung. Patients usually present in childhood with cough and recurrent pneumonia, and occasionally present with haemoptysis.