The mortality of tonsillitis is low, and usually lethal complications result from surgical intervention. According to the literature, the mortality rate following tonsillectomy equates to 1/1000–1/27,000 [2]. Complications of acute tonsillitis resulting in death include airway compromise secondary to airway obstruction and septicaemia due to systemic progression of the infection [4]. Airway compromise usually results from bilateral tonsillar enlargement. This phenomenon has also been reported in a 19-month-old boy with unilateral tonsillar enlargement, where a pedunculated left palatine tonsil occluded the glottis [5].
.Palatine tonsillar hypertrophy in infants is a common feature of both viral and bacterial tonsillitis, and has been postulated by Suzuki et al. [6] as a possible risk factor for Sudden and Unexplained Death in Infancy (SUDI), based on the theory of mechanical impediment of breathing by narrowing of the upper airway. It was further suggested that the degree of hypertrophy of the palatine tonsils appeared to be sufficient to narrow the upper airway from one or both sides of the pharynx and that the palatine tonsils might narrow the upper airway at the level of the pharynx, dependant on and facilitated by the sleeping position of the infant. This theory is on the face of it logical, yet deaths occurring as a result of uncomplicated, often significant infective tonsillar enlargement without surgical intervention are rare, or at the very least underreported. If enlarged tonsils can easily impact into the pharyngeal orifice, it is therefore quite surprising that deaths as a result of airway occlusion are apparently so rare.
Of importance to consider is also the relative size of the tonsils. The right palatine tonsil measured 32 mm (h) × 23 mm (w) and left tonsil 25 mm (h) × 21 mm (w). These dimensions need to be evaluated against the measured height and width of the tonsils as reported by Jong Hwan Wang et al. [7]. The subjective tonsil height in children between the ages of 3 years to 17 years old vary between 16,7 mm – 33,1 mm and the subjective tonsil width in this age group vary between 9,6 mm to 22,2 mm; however these subjective tonsillar sizes do not always correlate well with the actual tonsillar volume measured after tonsillectomy.
We postulate that the rounded shape of both hypertrophied tonsils in the pharynx may play a protective role with regards to the maintenance of a functional conduit through which respiration may be retained in the anterior, but apparently most prominently posterior aspect of the pharynx. As the tonsils protrude into the lumen of the pharynx, their rounded, expanded shape assures the formation of a triangular opening between the postero-medial aspects of the tonsils, and the posterior wall of the pharynx. This is clearly apparent on approximation of the incised posterior edges of the pharyngeal tissue block, not only in the fresh specimen, but also in the formalin fixed specimen. In our case, approximation of the pharyngeal ring and reconstitution of the enlarged tonsils to its in situ position results in a clearly identifiable opening measuring approximately 5 mm × 7 mm, even with the tonsils touching in the midline (Fig. 4). This aperture appears to be large enough to allow at least some air movement, when compared to the size of the pharyngeal aperture at the level of the cricoid cartilage in normal children. The epiglottis – a structure that is inconveniently located antero-inferior to this aperture formed by the posterior margins of the tonsils, can conceivably cause narrowing at this level if enlargement and edema of this structure and the surrounding superior laryngeal opening causes expansion of the tissue. In our case, the epiglottis and proximal laryngeal ring was indeed oedematous and exhibited signs of epiglottitis on histology.
Whereas there can be no doubt that massive tonsillar hypertrophy can in extreme cases cause critical airway obstruction, we postulate that the epiglottis may play a more significant role in the pathogenesis of sudden unexpected airway obstruction associated with tonsillar hypertrophy than previously suspected.
Byard et al. [5] emphasizes the need to examine the upper aerodigestive tract at autopsy in all age groups, not only early childhood, as such lesions may not produce marked symptoms and signs prior to lethal airway occlusion.