FIGURE 2 : Magnetic resonance venography with left common iliac vein ( arrow ) compressed by the right common iliac artery though MTS was identified as one of the causes , our patient had a history of bilateral leg swellings as well as intermittent face and upper extremity swelling with spontaneous resolution of symptoms with time . The cause of the upper body edema remains undiagnosed . that MTS could be the cause for the bilateral lower extremity swelling , but it could not account for the bilateral swelling of the hands and face . The underlying causes of the metabolic acidosis , headaches , and hematuria could also not be attributed to MTS and remained an enigma .
DISCUSSION
MTS is an anatomically and pathologically variable condition due to common iliac vein compression from an overlying right common iliac artery . This compression of the vessel can increase the risk for thrombotic events as well as cause symptoms of claudication , pain , swelling , and discoloration . In the case of partial venous obstruction , patients can be asymptomatic . The approach to diagnosis and treatment depends on whether venous thrombosis is present .
MTS was first described by May and Thurner in 1957 . 1 While the true incidence of MTS is not known as it is not typically identified in asymptomatic patients , it is predominantly seen in females with a mean age of 40 years . 2 Female patients present at a younger age and also outnumber male patients by a ratio of 2:1 . It has
been reported that MTS-related DVT tend to account for approximately 2 % to 3 % of all lower extremity DVT . 3 In most cases there are other causes of hypercoagulability ( e . g ., oral contraceptive use , dehydration , and smoking ). Even though MTS is mainly found in young adult patients , it has been seldomly reported in the pediatric population . 4 In their retro spective chart review of 17 patients age less than 18 years , Warad and colleagues reported a female predominance , and the median age was 15.4 years . In other published case reports , the finding of a DVT lead to the diagnosis in a 16-year-old female athlete and a 17-year-old adolescent boy . 1 , 4 Although the youngest reported case occurred in an 8-year-old-boy , 5 our case is unique in that MTS was diagnosed in such a relatively young boy of age 10 years .
There is no specific diagnostic marker for MTS , and digital subtraction venography still remains the gold standard for diagnosing it . In our case , the patient did not have a DVT and the diagnosis was made by the findings on MRI / MRA of pelvis and abdomen , which showed the classic finding of left common iliac vein compression by the right common iliac artery . Even
There are no clear guidelines for MTS management in children and adolescents . Treatment is usually reserved for symptomatic cases of MTS and usually includes the prescription of anticoagulants , thrombolytics , and angioplasty to reduce the risk of DVT . 3 Ultrasound-assisted catheter-directed local thrombolysis has been reported as a treatment option in teenage girls 6 and should be considered in children experiencing descending iliofemoral thrombosis . The study by Goldberg et al , including 95 children with median age of 16 years 7 who were treated with percutaneous mechanical thrombolysis and / or percutaneous pharmacomechanical thrombolysis had a technical success rate of 94 %. However , 40 % of these children in the study had early recurrent DVT and 27 % had late recurrence . In our case , the child was not a candidate for anticoagulants like warfarin since he is an active child with underlying diagnoses that increase his risk of injury and subsequent bleeding . Stent placement was not prescribed because of the lack of DVT .
CONCLUSION
Even though our patient with MTS is not the youngest reported in the literature , he is one of the youngest . His case brings awareness that MTS is a possible cause for lower extremity edema , even in non-athletes in the first decade of life . Our patient will need to be monitored closely over the years , as he had other symptomatology that could not be explained by the MTS diagnosis .
REFERENCES
1 . Gökçe Ş , Keskin G , Yaşar Ş K , Arslan AT , et al . A case of May-Thurner Syndrome : An old anomaly but , a new suggestion : A case report . Malawi Med J . 2019.31 ( 3 ): 230-232 .
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