A 45-yr-old man complained of low-back pain and sweating for the previous 4 mos. He described the pain as radiating toward the thighs on both sides, without any change during rest. His medical history included surgery for a mass lesion in the L3 vertebra 10 yrs earlier with similar complaints. Pathological evaluations had revealed hydatid cyst disease, and he had also been treated with antiparasitic therapy after surgery. Repeat magnetic resonance imaging 8 yrs after the surgery was normal, and he had only intermittent mild low-back pain during strenuous activities. The medical history was otherwise unremarkable.
At presentation, his vital signs were normal, with painful low-back motions and bilateral paravertebral muscle spasm. The straight leg raising test was positive bilaterally at 70°–80°. Results of the neurological examination of the lower limbs were normal. Laboratory findings were consistent with increased levels of lymphocytes, eosinophils, and C-reactive protein. The findings of chest x-ray were normal, but those of abdominal ultrasonography showed four inactive hydatid cysts in the liver. Magnetic resonance imaging of the low-back region also displayed vertebral cyst hydatidosis (Fig. 1).
Hydatid disease or hydatidosis, caused by Echinococcus granulosus, is the most widespread, serious human cestode infection in the world. The liver and the lungs are most frequently involved, and hydatid cysts of other organs are unusual. Bone involvement is reported in 0.5%–4% of the cases, and 50% of those are seen in the spine.1 Therefore, vertebral hydatidosis is uncommon; however, in endemic areas, physicians should be vigilant in case of relevant patients with mild symptoms, in whom the clinical scenario may well masquerade as other common low-back problems. In this aspect, magnetic resonance imaging could be used for prompt diagnosis.2
1. Awasthy N, Chand K: Primary hydatid disease of the spine: An unusual case. Br J Neurosurg
2. Karadeler S, Orakdögen M, Kiliç K, et al: Primary spinal extradural hydatid cyst in a child: Case report and review of the literature. Eur Spine J