Diagnosis and Management of Ureterohydronephrosis in Pregnancy

Introduction:

Pregnancy is a period during which females experience too many physical and mental transformations due to changes in the anatomical and physiological processes. This happens as the growing fetus changes the physical and hormonal balance of the mother. As a result of such changes, ladies can undergo several complications, and one of them is ureterohydronephrosis.

What Is Ureterohydronephrosis?

In any individual, when the urinary tract is obstructed, the organs in the urinary system (like the ureter) and the renal pelvis dilate to compensate for the obstructed urinary tract. The ureter and renal pelvis swell up in such cases, which is medically called ureterohydronephrosis.

Various Causes for Incidence of Ureterohydronephrosis:

• Obstruction in the ureteropelvic junction.

• Backward flow of urine in a condition called vesicoureteral reflux.

• Calculi (stone) in the kidney.

• Renal tumors.

• Stricture within the kidney.

• Physiologically, due to pregnancy as a result of fetal growth.

Obstruction due to any of the above causes increased intraluminal pressure, thus impeding the normal urinary flow (kidneys to the bladder), leading to the renal pelvis and ureter dilation. This is how ureterohydronephrosis results.

What Causes Ureterohydronephrosis in Pregnancy?

Ureterohydronephrosis is commonly seen to develop in the second trimester and continue till the third trimester of one’s pregnancy. Several etiological factors can be attributed to the incidence of ureterohydronephrosis in pregnant females:

• As the uterus enlarges structurally, pressure will be exerted on the ureters, particularly on the right side, due to the dextro-rotation of the uterus and the protective position of the sigmoid colon on the left side. This mechanical compression caused by the structural change can block the normal urine flow from the kidneys to the bladder, resulting in ureterohydronephrosis.

• Hormonal causes, like a peak in progesterone levels in pregnancy, cause smooth muscles to relax generally in the body. This includes smooth muscle relaxation in the ureters as well. Relaxation can lead to decreased peristalsis and further contribute to the stasis and subsequent dilation of the urinary tract (and resultant ureterohydronephrosis).

What Are the Symptoms of Ureterohydronephrosis in Pregnancy?

Some women may have symptoms in the urinary system when there is ureterohydronephrosis, and others may not have any. The common symptoms of ureterohydronephrosis in pregnancy include:

• The most common presentation of ureterohydronephrosis is flank pain. This will manifest as a dull, aching pain in the flank region, and when there is an acute infection in the ureter or kidney, the pain can shoot up acutely.

• Increased pressure on the bladder will be exerted in ureterohydronephrosis. This will cause the pregnant ladies to urinate very frequently.

• Urinary incontinence is also a common symptom accompanied by increased urinary frequency in ureterohydronephrosis.

• Some women may experience difficulty in urinating when affected by ureterohydronephrosis. This will be more evident when there is a concurrent urinary tract infection.

• Fever may sometimes indicate acute infection of the urinary system, like pyelonephritis.

• Shivering or chills.

• Generalized malaise.

• Generalized fatigue.

• Nausea.

• Vomiting.

• The presence of blood casts can be noted in urine in this condition.

• Discomfort in the lower abdomen can also be a symptom, often related to stress in the urinary system.

• Pain in the back, which can be mistaken for general pregnancy-related discomfort, may be more severe and persistent.

When the severity of ureterohydronephrosis is mild, women tend not to experience any of these symptoms and remain asymptomatic. However, in case of persistent pain and fever, pregnant ladies should never ignore the symptoms and have the renal system checked for the incidence of ureterohydronephrosis.

How to Diagnose Ureterohydronephrosis in Pregnancy?

• Ultrasonography is the most reliable and safest way to confirm the presence of ureterohydronephrosis in pregnancy. Ultrasound can reveal the extent of dilation in the renal pelvis and ureters and help differentiate between physiological and pathological causes.

• In advanced cases or women whose ultrasonography images are inconclusive, magnetic resonance imaging may be recommended to visualize the dilated pelvic structures. Magnetic resonance imaging refrains the affected women from exposure to ionizing radiation; hence, it is considered a safer imaging modality.

• Urinalysis and culture of urine samples obtained from the affected women will also be a part of the investigatory procedure. This helps to identify the presence of infection by checking for the levels of white blood cells, causative bacteria, and nitrites in the sample.

• Complete hematological investigations will be performed.

• To assess the impact of ureterohydronephrosis on the mother, renal function tests will be indicated.

How to Treat Ureterohydronephrosis in Pregnancy?

Conservative Management:

• When the symptoms of ureterohydronephrosis are very mild, conservative management options like increased fluid intake and regular ultrasonographic examination of the pelvic area will be advised.

• Antibiotics, antispasmodics, and analgesics that are deemed to be safe for use in pregnancy will be prescribed in case of incidence of urinary tract infection and associated pain.

Invasive Procedures for Managing Ureterohydronephrosis:

Invasive procedures will be indicated only when the obstruction is severe, and all the conservative treatment modalities have failed. This includes:

• Stent placement in the ureter relieves the obstruction and allows good urine flow.

• Percutaneous nephrostomy will be performed where a catheter will be placed directly into the renal pelvis (the region of obstruction), and the urine will be completely drained outside the body.

• If any investigation indicates the presence of an anatomical cause for obstruction in ureterohydronephrosis, it has to be surgically corrected, and this will be postponed only after the baby's birth.

What Are the Complications of Ureterohydronephrosis in Pregnancy?

• Obstruction in the tract structures or ureter can cause urine to remain stagnant. This creates an ideal and suitable environment for bacterial proliferation and can lead to pyelonephritis.

• When the renal pelvis and calyces are prolonged, there is increased intrarenal pressure, leading to ischemia and damage to renal parenchyma. This will manifest as acute kidney injury.

• Reduced urine output, along with increased serum creatinine levels, will be seen as a complication of ureterohydronephrosis in pregnancy.

• Severe pain and systemic infections such as pyelonephritis can induce the process of secreting inflammatory cytokines and prostaglandins. Thus, uterine contractions can occur suddenly, resulting in premature rupture of membranes. Such women tend to have preterm labor.

• Dysfunctional kidneys due to prolonged obstruction in ureterohydronephrosis can lead to fluid retention and altered regulation of blood pressure, thus resulting in preeclampsia. Also, the incidence of infections and systemic inflammation can exacerbate any previous or existing hypertensive disorders.

• Untreated urinary tract infections can escalate to urosepsis, leading to systemic inflammatory response syndrome.

Conclusion:

Ureterohydronephrosis is a common condition during pregnancy that generally arises due to physiological changes. Addressing the symptoms related to this condition immediately without postponing it can prevent severe infections and other complications. Protecting the mothers and the babies from the incidence and complications of ureterohydronephrosis is highly necessary and can be achieved by proper and vigilant medical care and monitoring.