Diagnostic evaluation for infectious etiology of sickle cell pain crisis

Asymptomatic bacteriuria in sickle cell disease: a cross-sectional study

Background

It is known that there is significant morbidity associated with urinary tract infection and with renal dysfunction in sickle cell disease (SCD). However, it is not known if there are potential adverse outcomes associated with asymptomatic bacteriuria (ASB) infections in sickle cell disease if left untreated. This study was undertaken to determine the prevalence of ASB, in a cohort of patients with SCD.

Methods

This is a cross-sectional study of patients in the Jamaican Sickle Cell Cohort. Aseptically collected mid-stream urine (MSU) samples were obtained from 266 patients for urinalysis, culture and sensitivity analysis. Proteinuria was measured by urine dipsticks. Individuals with abnormal urine culture results had repeat urine culture. Serum creatinine was measured and steady state haematology and uric acid concentrations were obtained from clinical records. This was completed at a primary care health clinic dedicated to sickle cell diseases in Kingston, Jamaica. There were 133 males and 133 females in the sample studied. The mean age (mean ± sd) of participants was 26.6 ± 2.5 years. The main outcome measures were the culture of ≥ 10⁵ colony forming units of a urinary tract pathogen per milliliter of urine from a MSU specimen on a single occasion (probable ASB) or on consecutive occasions (confirmed ASB).

Results

Of the 266 urines collected, 234 were sterile and 29 had significant bacteriuria yielding a prevalence of probable ASB of 10.9% (29/266). Fourteen patients had confirmed ASB (prevalence 5.3%) of which 13 had pyuria. Controlling for genotype, females were 14.7 times more likely to have confirmed ASB compared to males (95%CI 1.8 to 121.0). The number of recorded visits for symptomatic UTI was increased by a factor of 2.5 (95% CI 1.4 to 4.5, p < 0.005) but serum creatinine, uric acid and haematology values were not different in patients with confirmed ASB compared with those with sterile urine. There was no association with history of gram negative sepsis.

Conclusion

ASB is a significant problem in individuals with SCD and may be the source of pathogens in UTI. However, further research is needed to determine the clinical significance of ASB in SCD.

Urologic manifestations of hematologic disease sickle cell, leukemia, and thromboembolic disease

Advances in medicine are allowing patients with hematologic disease to live longer and healthier lives than ever before. As these patients age, however, manifestations of their disease processes may develop as complications in other organ systems. We discussed the major genitourinary complications of sickle cell anemia, leukemia, and thromboembolic disease. These range from the benign inability to concentrate urine that is seen in sickle cell disease to renal infarction that results from nephrotic syndrome. Our ability to treat and prevent these complications will improve as our understanding of these disease processes and their pathophysiology grows. Additionally, it is important for urologists to understand the underlying pathophysiology of hematologic disease to best serve the patients. For example, it may be the urologist who makes the diagnosis of ovarian vein thrombosis in a pregnant woman with right lower quadrant pain and fever. This diagnosis, with the proper treatment of antibiotics and anticoagulation, could prevent the potential development of septic thrombophlebitis. Urologists will increasingly be called upon to deal with the manifestations of these complex diseases as these patients are living longer. It is our duty to educate ourselves about these disease processes so that we can make the best clinical decisions for our patients.