https://orcid.org/0000-0002-6132-5779
It has been long known that high levels of homocysteine lead to vascular injury resulting in various health problems like atherosclerosis, venous thromboembolism, and obstetric complications.Citation1,Citation2 Furthermore, increased homocysteine levels may be the underlying factor behind many other diseases as homocysteine has a cytotoxic effect on several cell types.Citation3,Citation4 Cytotoxic effect of homocysteine may be one of the etiologic factors for the formation of gall and renal stones.Citation3,Citation4
I have read the manuscript written by Beksac et al. regarding the relationship between cholelithiasis and urolithiasis with methylenetetrahydrofolate reductase (MTHFR) polymorphisms with great interest.Citation5 The authors postulated that the presence of gall and renal stones may be associated with increased blood homocysteine levels and MTHFR polymorphisms in a specific group of patients with a poor obstetric history. Although this study revealed a relation between homocysteine levels and renal/gall stones, it did not discuss the possible pathophysiological mechanisms comprehensively. On the other hand, the determination of blood homocysteine cutoff values in predicting the presence of gall and renal stones is original and it may light the way of future studies. The optimal level of blood homocysteine level has been a matter of debate for many years. While some researchers claim that levels above 15 micromole/L are associated with increased risk for vascular complications, cutoff values for other health problems have not been determined yet.Citation6 It is interesting that the authors have found much lower homocysteine levels for gall and renal stones in this study. This may be due to the clinical characteristics of the study population, being aware of MTHFR polymorphisms (or folate/vitamin B12 deficiency) and intermittent use of vitamin B (especially folate). However, determining a cutoff value with a limited number of cases is a little bit pretentious.
Another important issue is the etiology-based approach of the authors for poor obstetric history. Medical practice for obstetric complications has been changed prominently in the last decade. Identification of risk factors, life-style modifications, appropriate management of preexisting health problems and adequate preconception counseling have become to be considered as key elements for achieving favorable pregnancy outcomes.Citation7,Citation8 Furthermore, the term “placenta mediated obstetric complications” has come to practice in the last years.Citation9 Many researchers revealed that various obstetric complications like miscarriage, fetal growth retardation, preeclampsia, intrauterine fetal demise, and placental abruption stem from the early stages of implantation and placentation. Thus, the management of risk factors for impaired placentation is crucial for a better pregnancy outcome. This manuscript is critical as the authors identified the risk factors of their patients based on a careful preconception counseling program. They originated their evaluation from the presence of gall and renal stones in order to find obstetric risk factors. However, they could not categorize the types of gall and renal stones and this seems to be an important limitation for their article. Additionally, conducting the study in a population with a relatively high rate of MTHFR polymorphisms may affect the determined homocysteine levels. On the other hand, the authors gave a good take-home message with this study. In my opinion, future, prospective, randomized studies with larger patient populations will reveal more accurate results.
Disclosure statement
No potential conflict of interest was reported by the author(s).
References
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