| disease | Nephroptosis |
Nephroptosis refers to a condition where the kidney moves beyond the normal range during respiratory activity, leading to symptoms related to the urinary system and other aspects. Normally, the kidney can move within 3 cm during respiration.
bubble_chart Etiology
The kidneys are located in the renal fossa on both sides between the thorax and the lumbar region. Due to the support of strong longitudinal muscles in the back and the fixation by abdominal organs, they generally do not shift excessively. However, because the lower part of the perirenal fat capsule is a potential loose space, the kidneys may descend when abdominal pressure decreases, leading to nephroptosis.
bubble_chart Clinical Manifestations
Nephroptosis is more common in young women. Our hospital analyzed a group of 100 cases of nephroptosis, with women accounting for 71%. The majority of patients were aged 20–40 (83%), which is related to the heavier physical load on young and middle-aged women, their childbearing age, relaxation of abdominal wall muscles after childbirth, and the sudden decrease in abdominal pressure postpartum.
The duration of the condition ranged from 6 months to 3 years in 60% of cases. Most patients were diagnosed when they sought medical attention for symptoms such as back pain, chronic urinary tract infections, or recurrent hematuria, and the affected kidney could be palpated.
The symptoms of nephroptosis can be broadly categorized into three types:
(1) Urinary symptoms: Lower back pain accounted for 92%. Over 50% of patients exhibited symptoms of chronic urinary tract infections, mostly urinary frequency and urgency, which are bladder irritation symptoms. One-third of cases also had a history of low-grade fever or recurrent fever. Occasionally, symptoms such as lower limb edema were observed.
(2) Digestive symptoms: Movement of the kidneys often causes traction on the celiac plexus, leading to gastrointestinal symptoms such as abdominal distension and fullness, nausea, vomiting, and reduced appetite.(3) Neurological Guanneng symptoms: Such patients are often nervous and may experience insomnia, dizziness, lack of strength, and memory decline, with an incidence rate of about 1/5.
The severity of these symptoms does not necessarily correlate with the degree of nephroptosis. Sometimes, even mild prolapse can cause significant symptoms.
Physical examination: 46% of cases exhibited costovertebral angle tenderness. The right kidney was palpable in 64% of cases, while the left kidney was palpable in 22%. Anatomically, the right kidney is positioned lower, and its renal fossa is shallower. Additionally, the impact from the liver makes right-sided nephroptosis more common than left-sided.
bubble_chart Treatment Measures
The treatment of nephroptosis can be divided into two main categories: ① Non-surgical treatment: Exercise the abdominal and lumbar muscles to increase intra-abdominal pressure and counteract kidney descent. This can be combined with oral Chinese patent drugs such as Tonifying Middle and Replenishing Qi Pills, Six-Ingredient Rehmannia Pills, etc., as well as medications that enhance protein synthesis like nandrolone phenylpropionate. Methods for exercising the abdominal muscles include sit-ups and straight-leg raises. Additionally, kidney braces or abdominal support belts can be used. ② Surgical treatment: a. Injection therapy: Inject colloidal or sponge-like agents made of quinine and gelatin around the kidney to induce perirenal adhesions and fix the kidney in place. b. Surgical fixation: In addition to making a small incision to insert quinine-gelatin agents around the kidney to create adhesions, the kidney can be completely separated from the perirenal fat and then fixed in its proper anatomical position using various methods.
(1) Medical History and Physical Examination Generally, based on the patient's complaints of urinary, gastrointestinal, and neurological Guanneng symptoms, as well as findings from the physical examination, a preliminary diagnosis can be made.
(2) X-ray Examination Intravenous pyelography must include a standing film at the end to assess the degree of mobility. However, since the standing film must be taken immediately upon standing (otherwise the contrast agent will be excreted and the kidneys will not be visible), the kidneys may not have descended to their usual position. In a study of 88 cases of nephroptosis at the Urology Department of Huashan Hospital in Shanghai, involving 176 kidneys, the mobility observed in the pyelograms was classified into three grades: - Grade I: Kidney mobility within one vertebral body. - Grade II: Kidney mobility within two vertebral bodies. - Grade III: Kidney mobility exceeding two vertebral bodies or accompanied by hydronephrosis or ureteral tortuosity. Additionally, some cases, though not showing descent in the pyelogram, could still be diagnosed as nephroptosis based on symptoms, physical examination, and ultrasound findings.
(3) Ultrasound Examination The degree of kidney mobility can be determined by comparing the kidney position after 30 minutes in a head-down position with its position after activity. In a study of 39 cases at Huashan Hospital, ultrasound findings matched intravenous pyelography in 74.3% of cases. Another 20.5% showed negative pyelography but correct ultrasound diagnosis, while only 2 cases had significant discrepancies. Thus, the overall diagnostic accuracy was 94.8%.
(4) Head-Down Bed Rest Test The patient is instructed to maintain a head-down, feet-up position for 3 days (e.g., by elevating the foot of the bed by the length of a brick). Urinalysis or hourly hematuria cell excretion rate is measured before, during, and after the test, and symptom relief is observed. If hematuria significantly decreases or disappears and symptoms improve, this supports a diagnosis of nephroptosis. If no improvement occurs, nephroptosis can be ruled out.
(5) Water Injection Test To determine whether the patient's lumbago originates from the kidney, water is injected into the renal pelvis via ureteral catheterization during cystoscopy until the patient feels distending pain in the lumbar region. If the pain's nature and location resemble the usual symptoms, the test is positive, supporting a diagnosis of nephroptosis. If not, the test is negative, indicating the symptoms are not due to nephroptosis.
Diagnostic Criteria: The severity of nephroptosis can be assessed by combining the patient's symptoms, signs, and X-ray findings.
- Grade I: Typical symptoms of lumbar soreness; the kidney is not palpable or only the root of the nose is felt. Some patients exhibit kidney tenderness. Intravenous pyelography shows kidney mobility within one vertebral body, and ultrasound shows mobility of 3 cm. There may be hematuria (mostly microscopic) or complications like urinary tract infections.
- Grade II: Clear symptoms of lumbar soreness accompanied by digestive and neurological Guanneng symptoms. The kidney is palpable. Pyelography shows mobility within two vertebral bodies, and ultrasound shows mobility between 3–6 cm. Most cases are accompanied by hematuria or urinary tract infections.
- Grade III: Clear symptoms and signs. Pyelography shows kidney mobility exceeding two vertebral bodies or, even if within two vertebral bodies, significant ureteral tortuosity, hydronephrosis, concurrent stones, or impaired renal function. Ultrasound shows kidney mobility exceeding 6 cm.
