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Respiratory symptoms of cough, wheeze, and breathlessness account for 40% of referrals to a general paediatric clinic. The majority of these children suffer from “wheeze secondary to upper respiratory tract infection” and “asthma”.
A 7 year old girl was referred by her general practitioner to the clinic with a two month history of persistent cough and recurrent wheeze; she had been treated for suspected asthma with fluticasone and salbutamol since early childhood. There was a history of infantile eczema. She was growing well on the 50th centile. General examination was normal. There was no cyanosis or clubbing. Respiratory and cardiovascular system examinations were unremarkable.
She had been admitted at the age of 14 months with cough and wheeze; chest x ray showed right lower lobe consolidation which improved on antibiotics. Both radiographs were studied and the pattern of curvilinear density (scimitar) in the right lower zone suggestive of scimitar syndrome was recognised. She was referred to the paediatric cardiology department for echocardiography, which showed dilated right atrium, right ventricle, and a branch of the right pulmonary vein draining into the inferior vena cava, a mild variant of scimitar syndrome.
A cardiac catheterisation and coil embolisation of the systemic pulmonary collateral from the descending aorta to the right lower lobe is scheduled.
Scimitar syndrome is a name given to the triad of: (1) curvilinear vascular density in the right lower zone; (2) hypoplastic right lung; and (3) dextroposition of the heart. It has a wide spectrum of presentation and may sometimes only present in adulthood with symptoms of wheeze, recurrent chest infections, or pulmonary hypertension.1
It remains a notoriously difficult diagnosis to make without a strong index of suspicion. In this case, pattern recognition on chest radiograph helped us to suspect the diagnosis. Examination and ECG may be entirely normal or just show right sided strain. Echocardiogram may also be normal or show dilated right sided chambers (as in this case). Diagnosis can be missed in up to 33% cases by echocardiography.2 More sensitive tests would include computed tomography scan, cardiac catheterisation, and magnetic resonance imaging with 3D MRA.3,4 Obstructive and early symptomatic types will usually need corrective surgery after stabilisation.5 Milder scimitar variant will probably do well with occlusion of the collateral supply.5
We have presented this case to highlight the fact that one has to keep an open mind regarding the final diagnosis in any child with recurrent wheeze, as all wheezes are not “asthma”.