In countries with a high standard of living the frequency is even higher. “It is a benign disease with significant medico-economic implications for the countries’ health systems. In addition, it is noted that lithiasis is a disease that recurs, as 50% of patients will have a stone reappear within the next 10 years, from the initial diagnosis.

The probability of symptomatic stone formation during pregnancy has been estimated at 1/200 to 1/1,500 pregnancies. It is a particularly painful condition, which can lead to serious complications, such as urinary tract inflammation, sepsis, premature birth, situations that threaten both the mother and the fetus”, points out Mr. Christos Papachristou, Urologist Surgeon – Andrologist, Director of the Urology Department of LETO.

Rationale

In pregnancy, several physiological and anatomical changes occur in the upper urinary tract:

• From the sixth week of pregnancy, normal hydronephrosis begins in 90% of pregnant women
• Increase in the size of the uterus
• Increased levels of progesterone, which cause a decrease in ureteral peristalsis
• Increase in glomerular filtration rate, increases urinary concentration of uric acid and calcium, substances that promote stone formation
• Changes in urine PH.

Symptoms

• Renal colic
• Hematuria
• Fever
• Nausea – vomiting
• Urinary frequency – urge to urinate.
There are several conditions that can mimic the symptoms of lithiasis and should be ruled out, such as:
• Appendicitis
• Diverticulitis
• Cholecystitis
• Placental abruption
• Early Childbirth.

Diagnosis

Kidney ultrasound: The first imaging test performed is the ultrasound of the kidneys. The use of ultrasound is safe, economical and can be repeated often, because no radiation is used. However, several times a diagnostic problem arises, because on the one hand it is not always possible to visualize the stone causing the obstruction, on the other hand because the normal stretching of the uterus due to pregnancy can also cause a similar clinical picture.

X-ray: Plain X-ray NOK is safe and can be used, since the amount of radiation to which the fetus is exposed is not more than 0.5mGy.

Magnetic resonance: MRI gives more information than ultrasound, however it has specific disadvantages such as:

• High cost
• Time consuming examination
• Small specialty in stone identification.

Computed Tomography: Computed tomography is not used as a routine examination, however the use of special low-radiation protocols is possible in cases where there is a differential diagnostic problem and the result of the examination will change the treatment plan.

Medication

“Pregnant women with urolithiasis may need two classes of drugs:

• Painkillers
• Antibiotics

The selections are not representative of the general population.

Acetaminophen and paracetamol are used as pain relievers safely throughout pregnancy. Similarly, opioids, which work in more painful situations. Regarding antibiotics, penicillins and cephalosporins can be used safely throughout pregnancy,” he says.

Treatment

“Pregnant women automatically pass stones more easily than the general population. Therefore, the primary treatment of the problem is always conservative,” he adds.

In 50-80% of pregnant women there will be an automatic expulsion of the stone.

• Extracorporeal lithotripsy in pregnant women is an absolute contraindication, due to the risks of the administered radiation as well as the harmful effects of the wave energy on the fetal tissues.
• Drainage of the system using a pig-tail ureteral catheter is often sufficient to relieve symptoms.
• An alternative way of draining the system is the placement of a percutaneous nephrostomy.
• A definitive solution to the problem is provided by intracorporeal lithotripsy using a laser, which can be applied at all stages of pregnancy.

“Treating a pregnant woman with urolithiasis is a challenge for the urologist. Factors such as the location and size of the stone, the intensity of the symptoms and the existence or not of inflammation play an important role in the decisions that will be made. The experience of the urologist in similar cases determines to a significant extent the final result”, concludes Mr. Papachristou.