What is a Tonsillolith?

Patient Presentation
A 17-year-old male came to clinic with halitosis for the past several days. He denied any fever or pain, and was performing oral hygiene at least 2x/day. He denied any allergic or upper respiratory tract infection symptoms. He also denied any foreign bodies, medications or drug use, or eating strong foods. The past medical history was positive for 2 strep throat infections over the past 6 months.

The pertinent physical exam showed a healthy male in no distress with normal vital signs and growth parameters. His ears and nose examination was normal. His oral examination found a white/yellow lesion within the right palatine tonsil. The tonsils did not show any erythema and were not enlarged. His teeth had good oral hygiene. The diagnosis of a tonsillolith was made. As the physician described the tonsillolith to the adolescent, he got a smile on his face and said, “That’s what I thought it was because it looked like the pictures on the Internet. I also spit out a hard thing about a month ago that sort of looked like that.” He was referred to his dentist for removal as it was causing problems and appeared to be recurrent by history.

Case Image
Figure 118 – Clinical image of a giant tonsillolith. From Thaker, 2008. Creative Commons License. Other images can be seen in the To Learn More below.

Discussion
Tonsillolith or tonsil stones are calcified structures that form in the palantine tonsillar crypts. The calculi are made up of calcium and other salts, along with microorganisms and other unidentified material (oral debris), that are likely caused by chronic irritation of the tonsil. Tonsilloliths often cause no problems and are an incidental finding on physical examination, but they can cause irritation, local pain, referred pain (to the ear), foreign body sensation, abscess and halitosis. Bacterial metabolism can cause volatile sulfur compounds and gases to be produced, thus causing oral halitosis. Tonsilloliths usually self-resolve, but they can also become dislodged and swallowed, or regurgitated as in the patient above.

Tonsilloliths are generally not common in the pediatric age range, but do occur and occur more in the teenage years. This may be because of differences in the pediatric population, but it also may be because of detection. One study of 482 patients in Japan who were being evaluated for head and neck concerns, found only 6 patients with tonsilloliths of the 30 patients who were < 19 years of age. This study evaluated panoramic radiographs versus computer tomography (CT) for tonsillolith detection. CT identified tonsilloliths more often, 46.1%, vs 7.6% for radiographs, CT also identified many tonsilloliths that were of smaller sizes (59 of then were < 2 mm in size). Radiographs detected no tonsilloliths that were < 2 mm and most were 3-5 mm in size. If dental imaging is performed for children, panoramic radiographs are used more often and therefore may not detect the tonsilloliths at all, and/or the tonsilloliths in children may be smaller and therefore not identified.

Learning Point
A tonsillolith is a living biofilm. The “[m]echanism of tonsillolith formation is due to the bacteria form[ing] a three-dimensional structure [with] dormant bacteria being in the center to serve as a constant nidus of biofilm.”

Bacteria adhere to the surface of the tonsil and secretes a slimy substance that holds the bacteria together in the tonsillar crypt. The adhesive substance is a polysaccharide that protects the bacteria against the body’s immune system. “Cell to cell signaling (quorum sensing) and communication with different bacteria enhances the biofilm formation.” Matrix calcification also appears to give further protection to the bacteria biofilm.

Aerobic and anaerobic microorganisms are present in tonsilloliths, with aerobic bacteria predominating on the external surface and anaerobic bacteria on the internal area.

Questions for Further Discussion
1. What are indications for referral for dental care?
2. What are indications for tonsillectomy? See Review here
3. What causes halitosis? See Review here

Related Cases

To Learn More
To view pediatric review articles on this topic from the past year check PubMed.

Evidence-based medicine information on this topic can be found at SearchingPediatrics.com, the National Guideline Clearinghouse and the Cochrane Database of Systematic Reviews.

Information prescriptions for patients can be found at MedlinePlus for this topic: Tonsils and Adenoids.

To view current news articles on this topic check Google News.

To view images related to this topic check Google Images.

To view videos related to this topic check YouTube Videos.

Thakur JS, Minhas RS, Thakur A, Sharma DR, Mohindroo NK. Giant tonsillolith causing odynophagia in a child: a rare case report. Cases J. 2008 Jul 18;1(1):50.

Babu TA, Joseph NM. Persistent earache due to tonsillolith. Indian Pediatr. 2012 Feb;49(2):144-5.

Oda M, Kito S, Tanaka T, Nishida I, Awano S, Fujita Y, et.al. Prevalence and imaging characteristics of detectable tonsilloliths on 482 pairs of consecutive CT and panoramic radiographs. BMC Oral Health. 2013 Oct 14;13:54.

Yellamma Bai K, Vinod Kumar B. Tonsillolith: A polymicrobial biofilm. Med J Armed Forces India. 2015 Jul;71(Suppl 1):S95-8.

Author
Donna M. D’Alessandro, MD
Professor of Pediatrics, University of Iowa Children’s Hospital