Low back pain is a very common cause of medical consultation and is especially common in the clinic of Urology due to lithiasic pathology. There are multiple diseases that can cause pain in this area and it is therefore essential to carry out a detailed anamnesis and a complete physical examination.PAIN LUMBAR, IS IT THE BACK OR THE KIDNEY?
WHAT ARE THE MOST FREQUENT CAUSES OF LUMBAR PAIN?
– Osteo-muscular (mechanical low back pain): this is the most frequent cause of back pain and its origin can be in the spine and / or paravertebral and lumbar muscles. Sometimes it can generate confusion regarding the differential diagnosis with nephritic colic. Typically it is a continuous pain that is exacerbated by movements and may give in at rest. It is not accompanied by urinary symptoms or nausea or vomiting.PAIN LUMBAR, IS IT THE BACK OR THE KIDNEY?
– Lithiasis in the urinary tract (nephritic colic): it is the second most frequent cause of low back pain. It is a pain of acute instauration and very intense and is secondary to the dilatation of the ureter after being obstructed by a stone. It usually originates in the lower back and can radiate to the abdomen and genitals. In addition, it is accompanied by urinary symptoms (stinging when urinating, increased urination frequency) and, sometimes, hematuria (blood in urine). On the other hand, it may be accompanied by vegetative symptoms (sweating, nausea and vomiting). It does not compromise with rest and has colic characteristics (intermittent-oscillating pain intensity).PAIN LUMBAR, IS IT THE BACK OR THE KIDNEY?
AT WHAT AGES DO PAIN APPEAR AND WHAT ARE THE RISK FACTORS?
– Mechanical low back pain: it is more frequent in adulthood although it can appear at any time of life. Occasionally, it may appear as a result of a lumbar trauma or after an effort (weight bearing, bad posture, …). Other associated factors are the affections of the spine (scoliosis, kyphosis, spondylolisthesis, herniated disc, etc.). Being overweight is a risk factor.PAIN LUMBAR, IS IT THE BACK OR THE KIDNEY?
– Nephritic colic: usually begins in young adults (between 20-40 years) and is slightly more frequent in males. Most times it is idiopathic (no cause is identified) although low water intake and sedentary lifestyle are risk factors. There are other factors such as repeated urinary infections and some metabolic disorders (eg hyperuricemia or gout, hypercalcemia, …).PAIN LUMBAR, IS IT THE BACK OR THE KIDNEY?
HOW IS IT DIAGNOSED?
– Mechanical low back pain: the physical examination is mandatory. Some forced postures can increase pain as well as pressure on the spine or muscle groups. The maneuvers of Lasègue and Bragard (mobilization of the leg in extension) can unmask a root compromise by compression of the nerve root in the vertebra. The realization of an x-ray can help to identify alterations of the spine and the nuclear magnetic resonance to study the intervertebral disc and the nerves.Nephritic colic: the characteristics of the pain as well as the urinary symptoms will make us think about the renal origin. The percussion of the lower back produces intense pain. The urine test usually shows the presence of blood or crystals from the stone. Reno-vesical ultrasonography can identify the stone as well as measure the degree of dilation of the urinary tract. The definitive test is the CT (Computerized Tomography or scanner) since it has the ability to identify almost all types of stones, in all locations and of any size, without the need to administer contrast. In addition, it gives you information about other organs and neighboring structures.PAIN LUMBAR, IS IT THE BACK OR THE KIDNEY?
WHAT TREATMENT DOES IT HAVE?
Both pathologies are usually treated with analgesia (intravenous or oral depending on the intensity of the symptoms). In the case of mechanical low back pain, it is recommended to avoid absolute rest in addition to hygienic-postural measures. Nephritic colic usually requires analgesic treatment maintained until the lithiasis is expelled. In the cases of persistence of the lithiasis, it will be necessary to propose a treatment for its fragmentation (lithotripsy, surgical intervention, etc …).PAIN LUMBAR, IS IT THE BACK OR THE KIDNEY?
With the use of clinical history, exploration and adequate tests, we will avoid erroneous diagnoses given the great similarity between the two main causes of low back pain; mechanical back pain and nephritic colic
Dr. Eduardo García Cruz
Low back pain is a very common condition and one of the main causes of work absenteeism today. Proper diagnosis and management can solve the underlying cause and cause complete remission of pain. With the use of clinical history, exploration and adequate tests, we will avoid erroneous diagnoses given the great similarity between the two main causes of low back pain; mechanical back pain and nephritic colic.PAIN LUMBAR, IS IT THE BACK OR THE KIDNEY?