Thrombocytosis as a Predictor of Serious Bacterial Infection in Febrile Infants

BACKGROUND

Most of the febrile infants <90 days old will have no more than a mild viral infection but there is a substantial minority that will be diagnosed as having serious bacterial infection at a reported prevalence of 10-14%. A simple, readily available, inexpensive diagnostic marker that yields results quickly and also accurately identifies bacterial infections in febrile infants would be of great value in management of these infants. This study aims to assess the role of thrombocytosis in predicting serious bacterial infection in young febrile infants beyond neonatal period.

METHODS

A hospital based cross-sectional observational study was conducted from May 2016 to April 2017 on 76 febrile infants of age group 29-90 days in Kanti Children's Hospital.

RESULTS

The incidence of serious bacterial infection was found 43 (56.6%). Thrombocytosis, elevated C-reactive protein and pyuria were significantly higher in serious bacterial infection cases (p value <0.05). Thrombocytosis alone had the sensitivity of only 53.5%, but had specificity of 90.9%. Elevated C-reactive protein had the best sensitivity (81.4%). Combination of leukocytosis, elevated C-reactive protein, pyuria and thrombocytosis had better sensitivity (93.0%) than these parameters alone. The overall ability of platelet count to identify infants with SBI was only moderate (AUC: 0.722). Elevated C-reactive protein was found to have better ability to identify infants with serious bacterial infection (AUC: 0.846).

CONCLUSIONS

Thrombocytosis is a common finding in young infants diagnosed with serious bacterial infection. It has however, moderate ability in identifying infants with serious bacterial infection. Combining thrombocytosis with elevated C-reactive protein, leukocytosis and pyuria has better sensitivity in diagnosing serious bacterial infection than these individual parameters alone. Hence, combining these parameters may help in early prediction of febrile young infants at risk of serious bacterial infection.

Lower urinary tract symptoms that predict microscopic pyuria

Introduction and hypothesis

Urinary dipsticks and culture analyses of a mid-stream urine specimen (MSU) at 10⁵ cfu ml⁻¹ of a known urinary pathogen are considered the gold standard investigations for diagnosing urinary tract infection (UTI). However, the reliability of these tests has been much criticised and they may mislead. It is now widely accepted that pyuria (≥1 WBC μl⁻¹) detected by microscopy of a fresh unspun, unstained specimen of urine is the best biological indicator of UTI available. We aimed to scrutinise the greater potential of symptoms analysis in detecting pyuria and UTI.

Methods

Lower urinary tract symptom (LUTS) descriptions were collected from patients with chronic lower urinary tract symptoms referred to a tertiary referral unit. The symptoms informed a 39-question inventory, grouped into storage, voiding, stress incontinence and pain symptoms. All questions sought a binary yes or no response. A bespoke software package was developed to collect the data. The study was powered to a sample of at least 1,990 patients, with sufficient power to analyse 39 symptoms in a linear model with an effect size of Cohen’s f² = 0.02, type 1 error probability = 0.05; and power (1-β); 95% where β is the probability of type 2 error). The inventory was administered to 2,050 female patients between August 2004 and November 2011. The data were collated and the following properties assessed: internal consistency, test–retest reliability, inter-observer reliability, internal responsiveness, external responsiveness, construct validity analysis and a comparison with the International Consultation on Incontinence Modular Questionnaire for female lower urinary tract symptoms (ICIQ-FLUTS). The dependent variable used as a surrogate marker of UTI was microscopic pyuria. An MSU sample was sent for routine culture.

Results

The symptoms proved reliable predictors of microscopic pyuria. In particular, voiding symptoms correlated well with microscopic pyuria (χ² = 88, df = 1, p < 0.001). The symptom inventory has significant psychometric characteristics as below: test–retest reliability: Cronbach’s alpha was 0.981; inter-observer reliability, Cronbach’s alpha was 0.995, internal responsiveness F = 221, p < 0.001, external responsiveness F = 359, df = 5, p < 0.001. The correlation coefficients for the domains of the ICIQ-FLUTS were around R = 0.5, p < 0.001.

Conclusion

This symptoms score performed well on the standard, psychometric validation. The score changed in response to treatment and in a direction appropriate to the changes in microscopic pyuria. It correlated with measures of quality of life. It would seem to make a good candidate for monitoring treatment progress in ordinary clinical practice.

Candidal psoas abscess following persistent pyuria in a renal transplant recipient

Candidal infections occur commonly in renal transplant recipients especially in genitourinary system. Although the epidemiology of candiduria has not been well characterized in renal transplant population, it is the most common cause of fungal infections. However, candidal psoas abscess is very rare in the literature. We report a 42-year-old male renal transplant recipient with prolonged pyuria and candiduria followed by candidal psoas abscess formation. The treatment consisted of prolonged antifungal therapy along with percutaneous drainage. However, eventually, a surgical drainage had to be performed for the successful eradication.

Significance of pyuria in the diagnosis of urinary tract infections in neonates

OBJECTIVES

To determine the significance of pyuria as a predictor of culture proven urinary tract infections (UTI) in neonates and to assess the frequency of urinary tract anomalies in neonates with pyuria.

METHODS

Prospective study conducted at the neonatal intensive care unit of a tertiary care hospital; (Liaquat National Hospital Karachi) for a period of 4 months from April 2008 to August 2008. One hundred and ten consecutive infants < or = 28 days of age admitted to the NICU of Liaquat National Hospital for medical reasons were included in the study. Information regarding age, gender, antenatal history, birth weight, clinical examination, laboratory findings and outcome were recorded on a questionnaire. Septic work up was performed and urine samples were collected using urethral catheterization. Patients showing any number of white blood cells on microscopy were included and their urine sent for culture. All patients had Ultrasound done during their hospital stay and those patients with any renal abnormality were further investigated with Micturating cyestoretherogram (MCUG) at 6 weeks.

RESULTS

Out of one hundred and ten patients admitted, thirty five patients showed the presence of pus cells in urine and were included in the study. Of the 35 neonates with pyuria, 71.4% had no growth in urine cultures and 38.2 % neonates with insignificant pyuria (< or = 9 cells in urine) showed a positive culture. The renal ultrasound was normal in 51.4% neonates with pyuria although it was abnormal in 100% of the subjects with higher number of pus cells in urine (> 20 pus cells).

CONCLUSION

Pyuria is not a useful marker for the diagnosis of culture proven UTI in neonates it cannot be used as an indicator of underlying renal abnormality, though it may have some utility in neonates with > 20 /numerous pus cells.

Acute focal bacterial nephritis in 25 children

Acute focal bacterial nephritis (AFBN), formerly known as lobar nephronia, is a rare form of interstitial bacterial nephritis. Most often described in adults with diabetes, there is only limited knowledge of AFBN in children. Ultrasound shows circular hypoechogenic, hypoperfused parenchyma lesions, which may be misdiagnosed as a renal abscess or tumor. From 1984 to 2005, AFBN was diagnosed in 30 children at the University Hospital Münster and the General Hospital Celle, Germany. Data of 25 cases (14 girls, 11 boys) were available for retrospective evaluation. Twenty-five children with AFBN, mean age 4.5 years (range: 0.25-17.5 years), were followed up on average 4.2 years (range: 0.5-11 years). All children were admitted to hospital due to fever and rapid deterioration of clinical condition, initially suspected of having meningitis (four patients), urinary tract infections (five patients), renal tumor (three patients), pneumonia (two patients), appendicitis (one patient), or with only unspecific symptoms (ten patients). AFBN was diagnosed by ultrasound on average 3 days (range: 1-10 days) after onset of symptoms. Pyuria was found in 18/25 children, bacteriuria in 20/25 children, and hematuria in one patient. Blood cultures were negative in all but one patient. Urinary tract abnormalities were found in 12 children, including vesicoureteral reflux (8), megaureter (1), urethral valves (1), unilateral renal hypoplasia (1), and one patient with megacystis, megaureter, caudal dystopic left kidney combined with hypoplasia and dysplasia of the right kidney. High-resolution ultrasound showed AFBN lesions to have resolved completely within 12 weeks after onset of intravenous antibiotic therapy in 20/25 children. Renal parenchymal cysts remained in three cases and focal scarring in two. Blood pressure and renal function was normal in 24/25 cases. AFBN should be suspected in children with fever and rapid deterioration of clinical condition. Residual lesions such as cysts or scarring of renal parenchyma could remain.

Asymptomatic bacteriuria: review and discussion of the IDSA guidelines

Asymptomatic bacteriuria is a common finding, but is usually benign. Screening and treatment of asymptomatic bacteriuria is only recommended for pregnant women, or for patients prior to selected invasive genitourinary procedures. Healthy women identified with asymptomatic bacteriuria on population screening subsequently experience more frequent episodes of symptomatic infection, but antimicrobial treatment of asymptomatic bacteriuria does not decrease the occurrence of these episodes. Clinical trials in spinal-cord injury patients, diabetic women, patients with indwelling urethral catheters, and elderly nursing home residents have consistently found no benefits with treatment of asymptomatic bacteriuria. Negative outcomes with antimicrobial treatment do occur, including adverse drug effects and re-infection with organisms of increasing resistance. Optimal management of asymptomatic bacteriuria requires appropriate implementation of screening strategies to promote timely identification of the selected patients for whom treatment is beneficial, and avoidance of antimicrobial therapy where no benefit has been shown.

Mycoplasma hominis and Ureaplasma urealyticum in patients with sterile pyuria

OBJECTIVES

Mycoplasma hominis and Ureaplasma urealyticum are associated with various diseases of the urogenital tract, but they are usually not detected by routine microbiological diagnosis. The aim of this study was to asses the prevalence of these organisms in patients with sterile pyuria.

METHODS

From December 2000 to June 2001 all urine samples sent in to microbiological diagnosis, which yielded > or =500 leucocytes/ml and <10(4) bacteria/ml, were collected for this study. Thirty-three samples from 30 patients (female: 21, male: nine; median age: 60 years, range: 23-91 years) met these criteria and were subjected to PCR for detection of M. hominis and U. urealyticum, respectively.

RESULTS

M. hominis and U. urealyticum were detected in 2 (7%) and 6 samples (20%), respectively. With regard to the underlying diseases of the patients, glomerulonephritis was significantly associated with the detection of urogenital mycoplasmas (p=0.02).

CONCLUSION

The prevalence of M. hominis and U. urealyticum found in this study corresponds to the expected prevalence in the general population. This finding does not indicate an association of sterile pyuria with urogenital mycoplasma infection/colonization.

[Clinical significance of Streptococcus agalactiae isolation from urine samples of outpatients from health care centers]

INTRODUCTION

Streptococcus agalactiae is a well-recognized pathogen in the obstetric population and is a cause of invasive infection in adults with underlying diseases. Nevertheless, the role of S. agalactiae in urinary tract infections in the adult non-pregnant population treated in outpatient health care centers has been less extensively studied.

METHODS

The clinical significance of S. agalactiae isolation in urine samples from health care center patients was studied in five areas of Spain over a period of six months. The study protocol included the collection of personal, epidemiological and clinical data. A total of 85 patients were studied; 79 were women (17 pregnant) and 6 men.

RESULTS

Pyuria was found in 72.9% of the cases. A total of 26.4% (n = 18) of non-pregnant women and all the men had some type of chronic underlying disease and 35.3% (n = 24) had urinary disease. Among the pregnant women, 53% had asymptomatic bacteriuria and 35.3% had vaginal and/or urethral colonization. Among the group of men and non-pregnant women, the most frequent entity was non-complicated cystitis, seen in 66.1% (45 of 68) of cases, followed by complicated infection in 19.1% and asymptomatic bacteriuria in 11.8%. Of the 45 patients with non-complicated cystitis, 35 (77.7%) were over 40 years old and 19 (42.2%) were over 60 years old.

CONCLUSIONS

Among the population of non-pregnant adults treated in outpatient health care centers, S. agalactiae isolation from urine was found mainly in women over 40 years old and was the cause of non-complicated urinary tract infection in more than half of cases.

Urinary Tract Infections: Does the Smell Really Tell?

Asymptomatic bacteriuria is considered a transient and benign condition in the geriatric population. Before a diagnosis of a urinary tract infection (UTI) can be made, symptoms and significant bacteriuria must be present. One of these symptoms is malodorous urine. Other symptoms of a UTI, typical in the younger population, have been found to be absent or misleading in the older adult population. Though early detection of UTIs improves outcomes, unnecessary laboratory tests are costly and time-consuming, and may encourage inappropriate antibiotic therapy. The purpose of this study was to determine if urine odor is an accurate predictor of a UTI in the older adult incontinent nursing home population. Ninety-seven recently wet incontinence pads of residents in six Midwestern nursing homes were evaluated for odor within 1 hour of voiding. These results were compared to microscopy and culture results of clean-catch urine samples from these individuals. Defining a UTI as either bacteriuria or bacteriuria and pyuria, using urine odor to identify a UTI resulted in error in one third of cases. Results of this study indicate smell of urine in incontinence pads may be an absent or misleading symptom for UTIs in elderly nursing home residents.

Resistance of uropathogens in symptomatic urinary tract infections in León, Nicaragua

Management of urinary tract infections (UTI) in Central America and especially Nicaragua, is complicated by the lack of knowledge about the antibiotic resistance of uropathogens. We conducted a prevalence study to gain more insight into the aetiology, bacterial resistance and risk factors for symptomatic UTI in the region of León, Nicaragua. In 2002, all consecutive patients with UTI symptoms and pyuria >/=10 WBC/hpf were admitted to the study. Positive cultures from midstream urine specimens were defined as >/=10(5) cfu/ml of a single uropathogen. Susceptibility tests were performed with disc diffusion tests using the Kirby-Bauer method and broth microdilution using National Committee for Clinical Laboratory Standards criteria both in León and a reference laboratory in Utrecht. A positive culture was present in 62 of 208 study subjects (30%). Escherichia coli (56%), Klebsiella spp. (18%) and Enterobacter spp. (11%) were the most frequent pathogens isolated. Presence of cystocele, incontinence and increasing age were risk factors for bacterial UTI. E. coli was least resistant to ceftriaxone, amikacin and nitrofurantoin (>90% susceptible). We observed high resistance rates in E. coli to amoxicillin (82%, MIC(90) 128 mg/l), trimethoprim-sulphamethoxazole (TMP-SMX) (64%, MIC(90) 32 mg/l), cephalothin (58%, MIC(90), 32 mg/l), ciprofloxacin (30%; MIC(90), 32 mg/l), amoxicillin/clavulanate (21%, MIC(90) 8 mg/l) and gentamicin (12%, MIC(90) 2 mg/l). Our results suggests that community acquired uropathogens in Nicaragua are highly resistant to many antimicrobial agents. The use of amoxicillin, trimethoprim-sulphamethoxazole and cephalothin against uropathogens needs to be reconsidered. High quinolone resistance rates among E. coli in Nicaragua gives cause for great concern.

Actinobaculum urinale sp. nov., from human urine

A hitherto undescribed Actinomyces-like bacterium was isolated from human urine. Based on its biochemical characteristics, the unidentified bacterium did not correspond to any currently described Actinomyces species or related taxa. Comparative 16S rRNA gene sequencing showed that the unknown bacterium exhibits a specific phylogenetic association with the genus Actinobaculum, but a sequence divergence of > 5% from the two currently recognized members of this genus, Actinobaculum schaalii and Actinobaculum suis, demonstrates that it represents a distinct species. Based on both phenotypic and 16S rRNA gene sequence considerations, it is proposed that the unknown bacterium from urine should be classified as a novel species, Actinobaculum urinale sp. nov. The type strain of Actinobaculum urinale is CCUG 46093(T) (= CIP 107424(T)).

Predicting urine culture results by dipstick testing and phase contrast microscopy

AIMS

Urine is the most frequently received clinical specimen for bacterial culture. To determine whether dipstick or microscopy results reliably predicted the presence or absence of a reportable urinary pathogen we performed dipstick testing and phase contrast microscopy on unspun urine from 500 specimens. We also investigated the relationship between the presence of squamous epithelial cells (SECs) and mixed growth on culture.

METHODS

For each specimen, the presence of leukocyte esterase and urinary nitrite was recorded as well as the quantity of leukocytes (WBC), SECs, and erythrocytes. All cultures had the number and type of each organism recorded. Pyuria was defined as > or =10 WBC/mm(3).

RESULTS

Specimens with <10 SEC/mm(3) had fewer isolates (0.9 isolate per culture) than specimens with > or =10 SEC/mm(3) (two isolates per culture); therefore, SEC contamination was defined as > or =10 SEC/mm(3). Of 500 specimens, 266 (53%) had no growth and 136 (27%) had mixed growth. A total of 288 (58%) specimens had negative dipstick results and completely normal microscopy. Of these, 11 (4%) had a pure growth of a urinary pathogen but the pathogen was present in only three (1%) at > or =10(5) CFU/mL. Of 413 urine specimens without SEC contamination, 323 (78%) had either no detectable growth or pure growth compared with only 41 of 87 (47%) with SEC contamination (P<0.001). Of the 413 urine specimens without SEC contamination, 90 (22%) had > or =2 organisms compared with 46 of 87 (53%) with contamination (P<0.01). Pyuria was present in only 21 of 266 (8%) urine specimens without growth but was present in 60 of 95 (64%) specimens containing a reportable pathogen (P<0.01).

CONCLUSIONS

SEC contamination does not reliably predict cultures with mixed growth, urine specimens with negative dipstick results and microscopy rarely contain a reportable urinary pathogen, and screening algorithms are warranted and justified.

[Effect of P fimbriae on pyuria and bacterial colonization of the human urinary tract]

This study investigated the role of P fimbriae in colonization of Escherichia coli, host response, and bacterial persistence in humans. Human volunteers were inoculated intravesically with the nonadherent ABU isolate E. coli 83972 and with P fimbriated transformants of the same strain. During the following 24 h all urine samples, and thereafter daily samples, were collected for urine culture, analysis of neutrophil numbers, and cytokine concentrations (IL-6 and IL-8). The P fimbriated transformants showed enhanced bacterial colonization in comparison to E. coli 83972 and lowered the bacterial numbers needed for persistent bacteriuria. The P fimbriated transformants also lowered the bacterial numbers needed for a significant neutrophil and cytokine host response. We conclude that P fimbriae enhance bacterial colonization and trigger the host response in the human urinary tract.

Measurement of cystatin-C and creatinine in urine

BACKGROUND

The concentration of serum cystatin-C (Cys-C) is highly correlated with creatinine (Cr), and is mainly determined by glomerular filtration; thus, Cys-C may be an index of the glomerular filtration rate (GFR). However, the kinetics of urinary Cys-C and Cr excretions are unclear. Thus, we investigated the kinetics of urinary Cys-C and Cr excretions, and examined whether the urinary Cys-C concentration can be used as a marker of renal function.

METHODS

The urinary excretion of Cys-C and Cr was evaluated in 1670 healthy subjects and 217 patients with proteinuria. We also investigated the urinary Cys-C concentration in 52 patients with chronic renal failure.

RESULTS

There was a good correlation between the urinary concentrations of Cys-C and Cr in the healthy group. This relation was also observed in patients showing persistent proteinuria without tubular cell damage. The mean urinary Cr concentration increased with age, and it was affected by the muscle mass. In contrast, the urinary Cys-C concentration was not affected by the muscle mass, and the concentration remained constant for all ages. We further found that the ratio of Cys-C to Cr (CCR) is a good index of the state of Cys-C reabsorption in the proximal tubules.

CONCLUSIONS

The urinary CCR can be a marker of renal tubular dysfunction. In addition, when CCR was in the normal range, the urinary Cys-C concentration accurately reflected the glomerular filtration function.

Use of urinary gram stain for detection of urinary tract infection in childhood

In this study, urinary culture, urinary Gram stain, and four tests within the urinalysis, leukocyte esterase, nitrite, microscopyfor bacteria, and microscopyforpyuria, were examined in 100 children with symptoms suggesting urinary tract infection. Our purpose was to determine the validity of the urinary Gram stain compared with a combination of pyuria plus Gram stain and overall urinalysis (positiveness of nitrite, leukocyte esterase, microscopy for bacteria, or microscopy for white blood cell). Of 100 children, aged two days to 15 years, 70 (70 percent) had a positive urinary culture: 40 girls (57 percent) and 30 boys (43 percent). Escherichia coli was the most common isolated agent. The sensitivity and specificity of the urinary Gram stain were 80 percent and 83 percent, and that of the combination of pyuria plus Gram stain 42 percent and 90 percent, and that of the overall urinalysis 74 percent and 3.5 percent respectively. Our findings revealed that neither method of urine screen should substitute for a urine culture in the symptomatic patients in childhood.

Urinary findings in asymptomatic subjects with spina bifida treated with intermittent catheterization

The urines from 43 asymptomatic children with spina bifida were examined. Eighty-one percent were abnormal because of bacteriuria and pyuria (51%), bacteriuria alone (26%) or pyuria alone (5%). Interleukin-8 was elevated in 54% of the abnormal urines. The presence of pyuria and interleukin 8 suggests that the asymptomatic bacteriuria reflects low grade infection rather than colonization.

Asymptomatic gonorrhoea and chlamydial infection in a population-based and work-site based sample of men in Kilimanjaro, Tanzania

The aim of this study was to screen healthy rural and urban Tanzanian men for chlamydial infection and gonorrhoea, and determine the prevalence and the predictive value of urethral symptoms, signs and pyuria. In 2 cross-sectional surveys, 796 men were interviewed regarding symptoms and examined for signs of urethritis. Gonorrhoea was detected by culture/gram-stained smears, Chlamydia trachomatis by antigen immunoassay, and pyuria by leukocyte esterase dipstick test. The prevalence of chlamydial infection, gonorrhoea and pyuria among rural men was 9.6%, 0.4%, and 12.7%, and among urban bar workers 7.4%, 8.1% and 6.3% respectively. Among all, 0.6% had urethral discharge confirmed by examination, while 2.6% reported urethral discharge and 7.4% dysuria. Among chlamydia-infected men, 59 (89%) of the 66 cases did not have urethritis symptoms or signs. Similarly, 24 (88%) of 28 men with gonorrhoea were asymptomatic. Treatment based on the urethral discharge sign, would have detected only one out of 92 cases with gonorrhoea and/or chlamydia in these populations.

The relationship between pyuria and infection in patients with indwelling urinary catheters: a prospective study of 761 patients

BACKGROUND

Pyuria is universally considered as essential for identifying urinary tract infections in noncatheterized patients. The utility of pyuria in the catheterized patient, to identify catheter-associated urinary tract infection (CAUTI), has not been adequately defined.

METHODS

We prospectively studied 761 newly catheterized patients in a university hospital; 82 (10.8%) developed nosocomial CAUTI (> 10(3) colony-forming units per milliliter). While catheterized, each patient was seen daily, a quantitative urine culture was obtained, and the urine white blood cell concentration was measured quantitatively using a hemocytometer.

RESULTS

The mean urine leukocyte count in patients with CAUTI was significantly higher than in patients without infections (71 vs 4 per microliter; P= .006). Pyuria was most strongly associated with CAUTI caused by gram-negative bacilli (white blood cell count, 121 vs 4 per microliter; P = .03); infection with coagulase-negative staphylococci and enterococci (white blood cell count, 39 vs 4 per microliter; P = .25) or yeasts (white blood cell count, 25 vs 4 per microliter; P = .15) produced much less pyuria. Pyuria with a white blood cell count greater than 10 per microliter (>5 per high-power field in a conventional urinalysis) had a specificity of 90% for predicting CAUTI with greater than 10(5) colony-forming units per milliliter but a sensitivity of only 37%.

CONCLUSIONS

In patients with short-term indwelling urinary catheters, pyuria is less strongly correlated with CAUTI than in noncatheterized patients with urinary tract infection. The strongest association is with CAUTI caused by gram-negative bacilli; the association is far weaker for infections caused by gram-positive cocci or yeasts. Most patients with CAUTI are asymptomatic and do not have associated fever. Pyuria should not be used as the sole criterion to obtain a urine culture in a patient with a catheter.

Asymptomatic bacteriuria and inflammatory response to urinary tract infection of elderly ambulatory women in nursing homes

BACKGROUND

Bacteriuria > or = 10(5) CFU/ml is evidence of urinary tract infection in the absence of associated signs or symptoms. The presence of pyuria with asymptomatic bacteriuria established the response of elderly women against microorganisms capable of causing invasiveness or tissue injury of the urinary tract.

METHODS

The association between bacteriuria and pyuria was determined in 178 elderly, ambulatory women without symptoms of urinary tract infection in seven nursing homes. Urine culture results were subsequently analyzed in conjunction with absolute leukocyte count in urine. In this cross-sectional study, asymptomatic bacteriuria in elderly women was classified with and without pyuria.

RESULTS

The prevalence of asymptomatic bacteriuria was found in 44 (24.7%) elderly women. The presence of pyuria had a sensitivity of 63.6% for bacteriuria and a specificity of 91%. The positive predictive value for the presence of pyuria predicting those with bacteriuria was 70%, and the negative predictive value for the absence of pyuria predicting those without bacteriuria was 88.4%. Escherichia coli was the most common organism isolated in 81.8% of the women.

CONCLUSIONS

Bacteriuria > or 10(5) CFU/ml associated with pyuria was detected in 77% of elderly women with asymptomatic urinary tract infections. Bacteriuria of < 10(5) CFU/ml with pyuria proves less sensitive as an indicator of urinary tract infection. Elderly women with pyuria but without bacteriuria should be studied for other causes of urinary tract inflammation.

Low bacterial counts in infants with urinary tract infection

We analyzed the number of colony-forming units in urine cultures obtained by suprapubic aspiration in a group of 366 unselected infants with symptomatic urinary tract infection to relate these findings to factors such as pyuria and vesicoureteric reflux. Seventy-three (20%) of 366 infants had fewer than 100,000 colony-forming units per milliliter. Such low counts were significantly related to low numbers of leukocytes in the urine. Vesicoureteric reflux was equally distributed among children, irrespective of the number of bacteria in quantitative culture. The findings emphasize the importance of sampling technique; in infants, the method of choice is suprapubic aspiration, or catheterization, which eliminates the risk that urinary tract infection is overlooked because of low bacterial counts.

A simple and efficient urine sampling method for bacteriological examination in elderly women

AIM

to determine how collecting urine voided directly into a container compares with urine obtained by suprapubic aspiration.

METHOD

urine samples were collected in a sterile recipient placed in the toilet or in the bed-pan during voiding, after the vulval region had been cleaned by water. These samples were compared with samples of the same urine obtained by suprapubic aspiration. The samples were examined for pyuria and bacteriuria. Applying the Kass criteria on the voided urine specimen and assessing the presence of leucocyturia, it was possible to differentiate urinary tract infection, asymptomatic bacteriuria and contamination.

RESULTS

all 13 cases of infection found on suprapubic aspiration were also identified by this sampling technique. The technique produced four false-positive results.

CONCLUSION

this simple sampling method may not only obviate the need for suprapubic aspiration but also for bladder catheterization in the diagnosis of urinary tract infection in many elderly women.

Does pyuria indicate infection in asymptomatic dialysis patients?

It has been suggested that the finding of leukocyturia > 10 WBC/HPF in asymptomatic dialysis patients predicts a positive urine culture and hence indicates urinary tract infection. Seventeen asymptomatic ESRD patients contributed clean catch specimens. Nine patients had ten or more WBC/HPF. One of these grew a possible pathogen in pure culture (23% of specimens excluding those growing multiple organisms). Thus, leukocyturia is not a good marker for positive urine culture and moreover is not demonstrated to indicate infection even when positive cultures follow.

Pyuria among chronically incontinent but otherwise asymptomatic nursing home residents

OBJECTIVE

To determine the prevalence of pyuria and its relationship to bacteriuria in a representative sample of chronically incontinent nursing home residents.

DESIGN

Prospective, descriptive case series.

SETTING

Six nursing homes.

PARTICIPANTS

Two hundred fourteen chronically incontinent, but otherwise asymptomatic, nursing home residents who were enrolled in a clinical intervention trial for urinary incontinence.

MEASURES

Two hundred fourteen urine specimens were collected by a validated clean catch technique. Each specimen underwent dipstick testing for leukocyte esterase, microscopic urinalysis to determine the number of white blood cells per high power field of centrifuged urine, and quantitative urine culture using standard laboratory techniques.

RESULTS

The overall prevalence of pyuria was 45%, as defined by > 10 white blood cells per high field of spun urine, and the overall prevalence of bacteriuria was 43%, as defined by the growth of > 100,000 colony forming units of a urinary pathogen. Fifty-nine percent of the specimens with bacteriuria and 34% of the specimens without bacteriuria had pyuria. Of specimens with pyuria, 56% had bacteriuria, and of specimens without pyuria, 31% had bacteriuria. When any colon change on the leukocyte esterase pad was considered positive, this finding had a sensitivity of 83% and a specificity of 52% for pyuria on microscopic urinalysis.

CONCLUSIONS

Pyuria is common among chronically incontinent nursing home residents, both in the presence and absence of bacteriuria. Clinicians must therefore be cautious in interpreting the presence of pyuria to indicate symptomatic infection in this population. Using pyuria to determine the need for antimicrobial treatment could result in unnecessary expense and morbidity as well as contribute to the development of resistant organisms in nursing homes. Research is needed to define pyuria better, to determine its prevalence and relationship to bacteriuria among nursing home residents with symptoms of acute urinary tract infection, and to elucidate the etiology and significance of sterile pyuria in this population.

Sterile pyuria: consider chlamydial infection

We report the cases of two men referred to a genitourinary medicine clinic with sterile pyuria and subsequently found to have their urethras infected with Chlamydia trachomatis. Chlamydial infection should be considered in the differential diagnosis of sterile pyuria, particularly in young, sexually active males. We discuss the consequences of inadequate treatment of the index case.

[Asymptomatic bacteriuria and pyuria during pregnancy]

BACKGROUND

The presence of pyuria and the role of mixed culture in the diagnosis of asymptomatic bacteriuria in pregnant women have been evaluated

METHODS

One hundred and sixty four pregnant women without any symptomatology have been studied using two cultures of mid-stream urine samples and pyuria quantification. In addition culture of bladder urine has been carried out in 17 of these patients (12 with pure cultures and 5 with mixed cultures).

RESULTS

110 samples were culture negative without pyuria; 7 were pure cultures with pyuria; 19 pure culture without pyuria and the remaining 28 patients yielded mixed culture with or without pyuria in the first culture. Twenty of these 28 mixed cultures were negative in the second culture. A estimated frequency of asymptomatic bacteriuria in pregnancy was 16% and pyuria was only found in 27% of pregnant women with asymptomatic bacteriuria.

CONCLUSION

The pyuria is not a useful marker for the diagnosis of asymptomatic bacteriuria in pregnancy.

A reassessment of the importance of "low-count" bacteriuria in young women with acute urinary symptoms

OBJECTIVE

To determine whether a statistical association exists between "low-count" bacteriuria (> 10(2) to 10(4) colony-forming units/mL) and acute urinary symptoms in young women.

DESIGN

Prospective, case-control study.

SETTING

Gynecology clinic at a student health center.

PATIENTS

Women with or without urinary or vaginal symptoms.

MEASUREMENTS

History of urinary infections and sexual activity. Quantitative determination of bacteriuria and pyuria and bacterial species; urine leukocyte esterase test; specific gravity; creatinine levels; vaginal leukocytes; and in-vitro culture of urine.

RESULTS

The frequency of recent sexual activity, pregnancies, and contraceptive practices was not statistically different between women with acute urinary symptoms and asymptomatic controls. Escherichia coli and Staphylococcus saprophyticus were the only microorganisms statistically associated with urinary symptoms and pyuria (P < 0.001). Low counts of these organisms were found in 10.2% of asymptomatic women. As the bacterial count increased, the association between these organisms and symptoms increased, and a step-wise increase occurred in the frequency and magnitude of pyuria, but the specific gravity and urine creatinine levels remained unchanged. Escherichia coli, even at low counts, grew well in the patients' own urine. Pyuria (> 20 leukocytes/mm3) was present in 19.6% of asymptomatic women and was associated with vaginal leukorrhea.

CONCLUSIONS

"Low-count" bacteriuria was statistically more frequent among young women with urinary symptoms than among asymptomatic controls. The low counts could not be explained by dilution of the urine or failure of the bacteria to grow well in the patients' urine. These findings suggest that the infection was not established in the bladder urine and that "low-count" bacteriuria might be an early phase of urinary tract infection.

Elevated prostate-specific antigen: a case report and analysis

Prostate cancer is a frequent concern of the clinician caring for older male patients. The certainty of arriving at the correct diagnosis is related to the presenting patient's risk for prostate cancer, the results of the digital rectal examination, and the value of the serum prostate-specific antigen (PSA). A case report of a patient with acute urinary retention and an elevated PSA is presented. Possible explanations for the elevated PSA are discussed. The clinician's intuitive thought process is compared with an analytic approach using calculated probabilities. Several factors that complicate the estimation of the likelihood of prostate cancer are discussed.

Evaluation of Questor urine screening system for bacteriuria and pyuria

AIMS

To evaluate the Questor automated bacteriuria and pyuria screening system; to compare its performance with that of a reference method; and to assess its usefulness in a routine clinical laboratory.

METHODS

The Questor urine screening system was compared with a comprehensive regimen to detect urinary tract infection, using pour-plate viable counts to determine the numbers of bacteria present in urine samples, a wide range of other cultural methods, microscopic findings and clinical information.

RESULTS

The optimal performance in detecting significant growths was a sensitivity of 93%, a specificity of 74%, a positive predictive value of 43% and a negative predictive value of 98%. The list price per test is 0.17 pounds and the capital cost of the system is 39,950 pounds. Questor can test 50 samples an hour and can be operated by one member of the laboratory staff, who is not required to make interpretative judgments--for example, a medical laboratory assistant.

CONCLUSIONS

The sensitivity and specificity of the Questor was better than that obtained from other screening systems using the same protocol. The system was easy to use and is a useful addition to the methods available for screening for bacteriuria.

Prevalence of urinary tract infection in febrile infants

Urinary tract infection (UTI), a relatively common cause of fever in infancy, usually consists of pyelonephritis and may cause permanent renal damage. This study assessed (1) the prevalence of UTI in febrile infants (temperature > or = 38.3 degrees C) with differing demographic and clinical characteristics and (2) the usefulness of urinalysis in diagnosing UTI. We diagnosed UTI in 50 (5.3%) of 945 febrile infants if we found > or = 10,000 colony-forming units of a single pathogen per milliliter in a urine specimen obtained by catheterization. Prevalences were similar in (1) infants aged < or = 2 months undergoing examination for sepsis (4.6%), (2) infants aged > 2 months in whom UTI was suspected, usually because no source of fever was apparent (5.9%), and (3) infants with no suspected UTI, most of whom had other illnesses (5.1%). Female and white infants had significantly more UTIs, respectively, than male and black infants. In all, 17% of white female infants with temperature > or = 39 degrees C had UTI, significantly more (p < 0.05) than any other grouping of infants by sex, race, and temperature. Febrile infants with no apparent source of fever were twice as likely to have UTI (7.5%) as those with a possible source of fever such as otitis media (3.5%) (p = 0.02). Only 1 (1.6%) of 62 subjects with an unequivocal source of fever, such as meningitis, had UTI. As indicators of UTI, pyuria and bacteriuria had sensitivities of 54% and 86% and specificities of 96% and 63%, respectively. In infants with fever, clinicians should consider UTI a potential source and consider a urine culture as part of the diagnostic evaluation.

Occurrence of pyuria and bacteriuria in asymptomatic hemodialysis patients

Patients with end-stage renal disease on hemodialysis have documented defects in their immune responses, and infections contribute significantly to their morbidity and mortality. This study prospectively detected and quantitated leukocyturia and bacteriuria in asymptomatic hemodialysis patients. Thirty-one percent of asymptomatic hemodialysis patients had significant pyuria (> 10 white blood cells per high-power field) and 25% had bacteriuria of pathologic dimensions, (> 1 x 10(5)/mL of a single microorganism). Pyuria was a good marker for significant bacteriuria in these patients. These results demonstrate that the urinary tract, even in ESRD patients on hemodialysis, may represent a significant reservoir for infection.

Criteria for the diagnosis of urinary tract infection and for the assessment of therapeutic effectiveness

Three parameters--urinary symptoms, pyuria, and bacteriuria--can be used independently or in combination to define the presence of urinary tract infection. Using these parameters, several approaches to defining urinary infection in various clinical contexts are discussed. Similarly, approaches to the definition and classification of therapeutic outcomes after antimicrobial treatment are explored. Further research is needed to more precisely evaluate the effectiveness of various criteria for diagnosis and cure of urinary infection.

First catch urine sediment for Chlamydia trachomatis and Neisseria gonorrhoeae culture in adolescent males with pyuria

Traditionally, only symptomatic males or those with a history of exposure are tested for sexually transmitted diseases (STDs). Since urethral infections with Chlamydia trachomatis and Neisseria gonorrhoeae are frequently asymptomatic, a practical, sensitive, and acceptable screening method is desirable. Fifty sexually active males with pyuria (age 13 to 22 years old) diagnosed with 1+ or 2+ leukocyte esterase (LE) dipstick on first catch urine (FCU) were further evaluated by culture of urethral swabs and centrifuged FCU samples for N. gonorrhoeae and C. trachomatis. Eighty-six percent had one or more positive cultures: 17 (34%) N. gonorrhoeae, 18 (36%) C. trachomatis, and 8 (16%) both organisms. FCU culture for N. gonorrhoeae had a 100% sensitivity, specificity, and positive and negative predictive value when compared to urethral swab cultures. FCU culture for C. trachomatis had a 32% sensitivity, 95% specificity, 89% positive predictive value, and a 53% negative predictive value compared to urethral culture. On the basis of the results of this study, one urethral swab can be eliminated when evaluating male adolescents for urethritis by using spun FCU culture for N. gonorrhoeae. Continued efforts should be made to develop optimal tests to detect STDs which are reliable and encourage compliance in this high-risk group.

[Urinary tract infection associated with urinary calculi. 1. The significance of urinary tract infection in urinary calculi]

We investigated 158 cases of urinary stones (infection stones 56, metabolic stones 102) with special reference to pyuria, bacteriuria, stone culture and urease activities of isolated bacteria. Abacterial pyuria was noted in 9 out of 49 (18%) infection stones and in 53 of 77 (69%) metabolic stones. Bacteriuria was noted in 79% of the infection stones and 26% of the metabolic stones. Sixty-seven percent of the infection stones were infected with mainly urea splitting bacteria such as Proteus mirabilis and Staphylococcus. Twenty-three percent of metabolic stones were also infected. Though E. coli, a non-urea splitting bacteria, was isolated most frequently from metabolic stones, urease positive Staphylococcus and Pseudomonas were also isolated. Bacteria within stones could be predicted on the basis of urine culture results of only 20 of 41 infection stones and 8 of 24 metabolic stones. These facts are useful for selection of some antibiotics in the treatment of urinary tract infections associated with urinary calculi. Urinary infections of urea splitting bacteria in infection stones are thought to be initial factors of stone formation and those of non-urea splitting bacteria are to be superimposed. However, urea splitting bacteria in metabolic stones may convert them into infection stones in future.

The prevalence of bacteriuria among high risk neonates in Nigeria

Among the 446 high risk neonates studied for significant bacteriuria and pyuria in the neonatal wards of the Obafemi Awolowo University teaching hospital Complex, Ile-Ife, 7.6% and 5.8% were positive for significant bacteriuria and pyuria respectively, while none of the 81 infants in the control group were positive. Males and females were similarly affected and there was no seasonal variation in the prevalence of pyuria or bacteriuria. It is noteworthy that 25 (96%) of the 26 pyuria neonates also had bacteriuria emphazising the significance of pyuria as a possible screening method for urinary tract infections in neonates. The clinical problems in the neonates studied included prematurity, low birthweight, neonatal jaundice, fever, CNS symptoms, ophthalmia neonatorum, prolonged rupture of the membranes (PROM), respiratory distress, septic cord/skin, diarrhoea, vomiting and feeding problems. Only prematurity and low birthweight were significantly associated with bacteriuria in the neonates studied. The organisms encountered in this study were Escherichia coli (58.4%), Klebsiella species (35.3%) and Proteus species (5.9%). Of the bacterial isolates, 67% were sensitive to Ampicillin and 97% to Gentamycin. The combination of these antibiotics was effective in all cases in the present study. The study has highlighted the need for routine urine culture in our high risk neonates.

Prostatic abscess owing to anaerobic bacteria

Abscess of the prostate is seen infrequently. We report a prostatic abscess owing to anaerobic bacteria in a 46-year-old man with a 10-year history of irritable voiding symptoms. Preoperative computerized tomography confirmed the diagnosis of prostatic abscess, which was treated with transurethral resection and broad-spectrum antibiotics.

[The course of pyuria after transurethral resection of the prostate and factor analysis of its duration]

The course of pyuria and bacteriuria was reviewed in 54 patients undergoing transurethral resection of prostate. Pyuria, which was seen in all cases, lasted for 70.1 +/- 24.7 days and bacteriuria defined as more than 10(4)/ml occurred in 16 patients (30%) postoperatively. To analyze the factors affecting the duration of pyuria, we utilized Hayashi's multidimensional quantification I theory. The factors included age, serum protein, preoperative indwelling catheter, preoperative urinary tract infection, resected weight, postoperative infection, the duration of postoperative indwelling catheter, and the way of antibacterial prophylaxis. The most important factor was resected weight (range 42.8 days), the second was postoperative infection (range 23.9 days) and the third preoperative infection (range 20.9 days). The other factors had no significance. Our analysis showed good correlation between the observed and predicted duration of pyuria (r = 0.82, p less than 0.005).

Streptococci as urinary pathogens

In a 2-month prospective study of streptococci isolated from urine specimens in the laboratory, 242 strains of catalase-negative gram-positive cocci or coccobacilli were isolated in substantial numbers from 11,725 specimens. These comprised 10% of the important isolates. Species identification of all isolates was undertaken. 74 (30%) of the isolates were of species other than Streptococcus faecalis and S agalactiae. 79 (33%) were not detected on cysteine-lactose-electrolyte-deficient agar after overnight incubation in a carbon dioxide incubator. 20 of the 24 isolates of coccobacilli were Gardnerella vaginalis. Many of the isolates of fastidious species were accompanied by pyuria. An isolation protocol practicable in busy laboratories is proposed.