A Rare Cause of Chronic Low Back Pain: Paravertebral Hydatid Cyst

              Hydatid cyst (HC) is a parasitic disease, generally affecting the ones having close contact with animas like dogs and cats. The disease is prevalent in Mediterranean countries, Africa, South America, New Zealand, and Southern Australia [1]. It may affect any organ and tissue in the body, in particular the liver (75%) and lung (15%). Primary subcutaneous hydatid cyst affecting posterior paravertebral muscle is a very rare condition even in endemic areas [2,3].            A 48-year-old man was admitted to our outpatient clinic with low back and right leg pain for 1 year. Lumbar spinal movements were painful and the pain radiated to his right posterolateral thigh. There was no weakness and numbness in both lower limbs but he had difficulty in load transfer during walking and therefore had ambulation difficulty. Tendon reflexes, and muscle strength examinations were normal. There was a slightly swelling at the right lumbar paravertebral region of spine by palpation. Routine blood tests were normal. Lumbar magnetic resonance examination (MRI) was requested for clear evaluation of lower back structures. In MRI, we found a 8 × 5 cm multicystic mass at the level of L3–S3 located at the right paravertebral muscle. After this diagnosis, the patient began receiving albendazol.  Total cyst resection was performed and the histopathological examination confirmed hydatic cyst.