Altered bladder function in staghorn calculus disease

Annual changes of the incidence and clinical characteristics of magnesium ammonium phosphate urinary stones

BACKGROUND

Magnesium ammonium phosphate (MAP) urinary stones account for the majority of staghorn stones and frequently cause a non-functioning kidney. In the present study, we examined the annual changes of the number and clinical characteristics of MAP stones.

METHODS

The annual incidence of MAP stones was investigated in 2619 patients with urinary stones in whom composition of the stone was analysed at Chiba University Hospital between 1964 and 1999. In addition, the annual number of patients with MAP stones was examined at Funabashi Clinic. In a total of 644 patients with MAP stones, age and sex of the patients, location and size of the MAP stones, urinary cultures and etiological factors were analysed.

RESULTS

The number of MAP stones in the lower urinary tract was relatively constant. In contrast, MAP stones in the upper urinary tract had dramatically decreased since 1989, resulting in an increase in the rate of MAP stones in the lower urinary tract. Age distribution of the MAP stone patients ranged from 10 years to > 80 years, with the majority aged 30-60 years. The proportion of larger MAP stones in the upper urinary tract increased. There was no significant difference in prevalence of urine cultures. Among etiological factors for MAP stones, difficulty on urination tended to be common in recent years.

CONCLUSION

The number of MAP stones, especially in upper urinary tract, has been decreasing during the last decade. At present, treatment of urinary tract obstruction seems important for the management of MAP stones in lower urinary tract.

Renal stone disease in children

Renal stone disease has been regarded as an uncommon problem in children compared to adults. However, increased awareness of this problem in children may lead to early intervention preventing long-term consequences on the kidney and the urinary tract. This article reviews the epidemiology, pathogenesis, and the most common etiologies of renal stones in children. The clinical features and diagnostic and therapeutic modalities for the specific etiologies are also outlined. Using these guidelines may be helpful not only in the treatment but also in the prevention of renal stones.

Treatment options in struvite stones

Urinary calculi have plagued man over the centuries. The epidemiology and pathogenesis of infection have been studied. The curative treatment remains problematic. Without therapy, a vicious cycle of stone formation occurs. This results in renal damage and even death. Multimodality therapy is the key. Nonoperative treatment leads to progressive renal damage. The combination of maximal surgical ablation and medical therapy is synergistic. The combination of PCNL-ESWL has not appeared to produce ill effects. PCNL-ESWL is a less morbid surgical alternative than open surgical procedures. Adjunctive medical therapy, such as culture-specific antibiotics and urease inhibitors, complements surgical ablation by reducing the morbidity with persistent UTIs and stone recurrence. The urologist today must approach struvite staghorns with a vast armamentarium of surgical and medical techniques. Each patient requires a unique solution.

Infection stones

The pathogenesis and epidemiology of infection stones are well understood. While percutaneous lithotripsy and extracorporeal shock wave lithotripsy have emerged as the mainstay of extirpative therapy, surgical lithotomy is the standard to which other therapies must be compared. Adjunctive therapy with pharmacological agents that inhibit urease with few side effects and effective urinary acidifiers favor chemolysis. Diet and chemotherapy offer the hope of slowing stone growth and/or recurrence in patients with chronic urease-producing bacteriuria.

The severity of infection stones compared to other stones in the upper urinary tract

A retrospective study of the case records of 391 adult patients with spontaneously passed or surgically removed concrements from the upper urinary tract during the period 1982-1983 was performed. According to chemical analysis, 66% of the stones were calcium stones, 30% were infection stones, 4% were uric acid/urate stones and 1% were cystine stones. Of the infection stones 12 (10%) were staghorn calculi. The infection stones placed a greater strain on the patients than the calcium stones. Thus, infection stones were significantly more often recurrent stones and required surgery significantly more often than the calcium stones. Only 6% of the patients with infection stones had proved abnormalities predisposing to upper urinary tract infection. Urinary tract infection with a urease-producing microorganism was detected in only 52% of the patients with infection stones. As infection with a urease-producing microorganism is a prerequisite for the formation of infection stones in the urinary tract a careful microbiological investigation to find and treat the infection responsible for the stone formation is mandatory.

Predicting lower urinary tract dysfunctions in patients with spinal cord injury

The results of combined cystometry and perineal electromyography were reviewed retrospectively in 75 consecutive, traumatic spinal cord-injured patients to predict lower urinary tract dysfunctions. In patients with vertebral spinal injuries at vertebral level T7 or above a reflex neurogenic bladder eventually developed. In those with vertebral level injuries T11 or below a lower motor neuron bladder dysfunction developed. Injuries at the vertebral levels T8, T9, and T10 represent a gray zone; and, depending on adjacent soft tissue injury, in these patients an upper or lower motor neuron bladder dysfunction developed. In transition from spinal shock (areflexia) to reflex neurogenic (hyperreflexia) bladder occurred at different times in different patients and could not be correlated to level of injury or its severity. The periurethral striated muscle was generally denervated if a lower motor neuron bladder dysfunction existed, however, rarely, dissociation may occur. When a reflex neurogenic bladder existed, sphincter dyssynergia was present 68 per cent of the time. This also could not be correlated with time after injury, level of injury, or severity of injury.

Cystometric and perineal electromyography in spinal cord-injured patients

The results of combined cystometry and perineal electromyography were reviewed retrospectively in 50 consecutive, traumatic spinal cord-injured patients. Early and frequent urodynamic evaluation was found necessary in order to tailor treatment to the changing cystometric and electromyographic states in these patients.