Enzymatic study of tonsil tissue alkaline and acid phosphatase in children with recurrent tonsillitis and tonsil hypertrophy.

Objective: Indications for tonsillectomy in recurrent tonsillitis are defined according to the number of episodes of acute bacterial infections in a year. However, little is known about the tonsil immune competence status in patients presenting with recurrent tonsillitis with either hypertrophied or atrophied tonsils, or in patients presenting with obstructive sleep apnoea. In this study we examined the tonsil immune status in children with 3-5 acute recurrent infections a year and in children with obstructive sleep apnoea by comparing the activity of tonsil and adenoid tissue nonspecific alkaline and acid phosphatase.

Methods: Specific activity of tonsil and adenoid tissue nonspecific alkaline and acid phosphatase was investigated in children who underwent tonsillectomy and adenoidectomy for recurrent infection (72 children) and for obstructive sleep apnoea (10 children). Tissue enzyme activities were measured using p-nitrophenylphosphate as a substrate. Tissue samples were examined by the haematoxylin-eosin histological technique. Statistical analyses were performed using SPSS v. 16 software.

Results: The tissue nonspecific alkaline phosphatase activity was similar in hypertrophied tonsils in the recurrent infection group and in the obstructive sleep apnoea group (3.437+/-1.226 and 3.978+/-0.762 U/mg of protein, respectively). The enzyme activity in both hypertrophied tonsil groups was significantly higher as compared to atrophied tonsils in the recurrent tonsillitis group, p=0.021 and p=0.006, respectively. The enzyme activity was significantly higher in the adenoids compared to the tonsils from all three groups. Contrary to this, no significant differences were noticed for tonsil and adenoid acid phosphatase activities among the groups.

Conclusion: Similar acid phosphatase activity in all three groups implies that all three groups have preserved antigen presenting cell activity. In patients with hypertrophied tonsils similar tissue nonspecific alkaline phosphatase activity suggests preserved B cell tonsil immune activity, regardless of the pathology. Patients with atrophied tonsils had significantly lower alkaline phosphatase activity, indicating relative tonsil B cell immune deficiency. Thus, different immunological status in patients presenting with hypertrophied vs. atrophied tonsils could point to a different underlying pathophysiologic mechanism of the disease.