Dental complications in homocystinurias

Background

Cystathionine beta synthase deficiency (causing classical homocystinuria) has been associated with high-arched palates and crowded teeth, but little has been said about other oral health complications. Other homocystinurias (e.g., the remethylation defects) also have had little reported in terms of oral health. Individuals with the homocystinurias have been described as having bone density issues which can correlate with oral health. Moreover, elevations in homocysteine have a theoretical impact on tooth health and the paucity of clinical reports of oral health issues in homocystinuria may be the consequence of lack of attention by the medical community.

Significance

Oral health is essential to overall health. If inadequate attention is paid to the oral health complications which can be seen in homocystinurias, then appropriate referrals and attention in therapeutic guidelines will not reflect the importance of oral health.

Specific aims/research question

What oral health complications are reported by individuals with homocystinurias? Do these differ according to diagnosis?

Methods

Data were collected from patients with homocystinurias by a series of questionnaires using the RARE-X platform. All subjects were consented prior to the collection of their data. All research was performed in accordance with the Declaration of Helsinki. Demographic data were collected as the initial questionnaire and other data were collected via the oral health questionnaire.

Analysis

Questionnaires were opened to the community in mid-2022 and collection of data for this study ended with data submitted up to November 2022. Descriptive statistics were done. Due to the small size of the cohort, additional statistical analyses were not attempted.

Results

Patients with homocystinuria, not related to cystathionine beta synthase deficiency, are reporting some tooth structure differences. The cohort taken as a whole does not have increased risk for gingivitis, but there appears to be a risk for long-term gum disease possibly due to the rate of osteoporosis/osteopenia in this population. A large number of individuals have malalignment and malocclusion of the teeth. These data highlight oral health as an important component of care in individuals with the homocystinurias as is true of the general population at large.

Methylene Tetrahydrofolate Reductase Deficiency

5,10-Methylene-tetrahydrofolate reductase (MTHFR) deficiency is a rare, autosomal recessive, metabolic disorder of folate metabolism, which affects homocysteine remethylation. Elevated homocysteine with normal or low methionine level is the key to diagnosis. Early recognition and treatment with betaine, has been shown to improve the survival and neurological outcomes. The authors report five Indian patients from three unrelated families, with MTHFR deficiency to emphasize the importance of early recognition and initiation of specific treatment.

Methylene Tetrahydrofolate Reductase Deficiency: the Hidden Risk in Paediatric Anaesthesia

Objective

Methylene tetrahydrofolate reductase (MTHFR) deficiency is an autosomal recessive disorder that results in increased homocysteine levels in the body. Hyperhomocysteinemia causes a predisposition to venous and arterial thrombosis and ischaemic insults. The incidence of the deficiency is around 40% in some countries. In this study, we aimed to evaluate the effects of anaesthetic agents in children with MTHFR deficiency.

Methods

Twelve paediatric patients with an MTHFR enzyme deficiency who underwent surgery in a ten-month period in a single centre were retrospectively evaluated. Demographic data, homocysteine levels before and after surgery, anaesthesia management and postoperative complications were recorded.

Results

In four patients, propofol was used both for anaesthesia induction and total intravenous anaesthesia (TIVA). Eight patients received sevoflurane for both induction and maintenance of anaesthesia. Nitrous oxide (N₂O) was not used in any patients. There was not a significant difference between the preoperative and postoperative homocysteine levels (p>0.05). Twenty-four hours after the surgery, the homocysteine levels were within normal limits. No complications were observed.

Conclusion

Sevoflurane and propofol have no deleterious effects on homocysteine levels in patients with MTHFR deficiency. Avoidance of N₂O is the key point for anaesthetic consideration regarding these patients.