Discussion and conclusion
Children like to take pieces of toys or food into their mouths and keep them inside while running and playing, so when they fall, they easily aspirate them. This worldwide phenomenon is well- known, however inhalation of grass head is extremely rare. The difference between inhalation of grass inflorescence, or other foreign bodies is mainly due to their shape. A smooth, round object merely overlies the mucosa, however, grass head with its several spikes can migrate towards the periphery. Historically, Chevalier Jackson (1952) was the first to classify grass inflorescences into two different types based on their structure. A small proportion of the grass called the “lodging” type, remains in the respiratory tract and causes pneumonitis. However, the majority, called “extrusive” type travel to the periphery of the lung. Migration continues with each coughing or respiratory action until the grass head finally penetrates through the lung and chest wall, and extrudes spontaneously [
1,
6‐
8]. Immediate bronchoscopy may diagnose some of the “lodging” type heads in a major bronchus [
9], but the majority, including the “extrusive” type, rapidly migrate deep beyond the reach of the bronchoscope.
After a few days, as the grass head travels continuously towards the periphery of the lung, initial signs and symptoms may disappear. The following asymptomatic period, with negative bronchoscopy, may create a false sense of security in physicians and parents alike. However, negative bronchoscopy or improved inflammatory markers do not exclude the presence of a bronchial grass head.
Aspiration of grass head is so rare phenomenon, that only few cases were reported in children, and most physicians has limited experience with them. With our two cases we provide diagnostic and management steps to reduce damage and to prevent developing complications.
Reviewing the literature for grass head aspiration in children, the most frequent notated outcomes caused by the grass head migration are chest wall abscess, bronchopleural cutaneous fistula and extrusion of grass head through the chest wall [
6‐
8], pneumothorax [
2], pneumomediastinum, recurrent haemoptysis, pleural effusion, bronchiectasis [
4], empyema, or osteomyelitis of the rib [
1], brain abscess or coexisting acute abdomen [
5,
8].
Literary data is consistent, that all the cases with suspicion of a grass head aspiration should immediately be referred for bronchoscopy [
1,
3,
6,
9]. However, the removal can only be accomplished before peripheral migration [
9]. Due to the anatomical structure of the main bronchi, an aspirated foreign body (including grass heads) is most likely present in the right lower bronchial tree, therefore examination of the right lower lobe during bronchoscopy should be emphasised. According to the revised literature, compared to only 1 left sided case, 15 cases showed inhalation into the right lower lobe [
1‐
9]. Both of our cases showed grass heads in the right lower lobe.
According to the aforementioned rapid migration negative bronchoscopic result do not exclude the presence of bronchial grass head, thus symptomless child with improved inflammatory markers should be followed up thoroughly. Regular chest ultrasound and X-ray is strongly recommended to recognise inflammation and also potential late-onset, life-threatening complications in time. If the examinations show (localising) inflammation computed tomography can be a useful diagnostic tool in identifying the foreign body, and revealing complications. In our cases despite the fact, that both of our patients showed improvement of symptoms, computed tomographic examinations detected bronchiectasis in Case 1 and early stage abscess formation in Case 2, 6 months and 32 days after the aspiration, respectively, suggesting the presence of a foreign body.
Literature provides no exact protocol on “wait-and-see” or surgery. The majority of data state that delayed treatment can be potentially life-endangering and also suggest to perform lobectomy. In order to prevent the above mentioned complications we agree on early surgical exploration of the involved lung. The optimal time for surgical intervention can be determinated by signs of localised inflammation seen on chest X-ray or CT. Despite the fact that pulmonary inflammation may temporarily improve or even vanish, a surgical management should be strongly considered to prevent life-threatening, late complications.
During the first case, 6 months after aspiration, typical features of bronchiectasis were seen on chest X-ray, while in the second case, 32 days after aspiration, an abscess was primarily detected, with successful surgical removal in both cases.
During the first case, due to late diagnosis and extensive pulmonary inflammation, right inferior lobectomy had to be carried out. In the second case, due to localised inflammatory signs, resection of the right 6th segment was satisfactory. According to literature data, lobectomy is most frequently preferred for removal of grass heads [
1,
3,
4,
9], with no previous publications of segmentectomy in case of children.
In conclusion we declare that the diagnosis of suspected grass head inhalation may lead to difficulties due to its peculiar shape and behaviour. Negative bronchoscopic result and improved inflammatory markers do not exclude the presence of bronchial grass head, thus symptomless child should be followed up thoroughly to recognise late complications in time. Regular diagnostic steps (such as chest ultrasound or X-ray) should be performed to localise inflammation. Chest CT maybe useful to confirm the diagnosis and identify the position of the foreign body. Surgical removal is opted when the grass head states peripheral, and localised inflammation evolves but before severe complications develop. In case that awn is found in a completely localized inflammation site or abscess, anatomical segmentectomy with the affected bronchus may be the preferred choice. In case of extended inflammation and abscess, or in obscure conditions, lobectomy may be required.
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