Renal Parenchymal Echogenicity Research Articles

Fetal renal parenchyma: Evaluation of a novel ultrasound measurement to assess kidney development

Introduction Abnormal fetal growth can adversely impact renal development and is associated with increased risks of developing hypertension and chronic kidney disease later in life. A non-invasive, sensitive method of assessing normal and abnormal fetal kidney development is required. We hypothesise that the fetal renal parenchymal thickness could be used to evaluate the development of the fetal kidneys and provide an indirect estimate of fetal nephron number. This study uses antenatal ultrasound to assess fetal renal parenchymal growth and blood flow to determine if these are affected by abnormal fetal growth. Methods A longitudinal, observational study was conducted at the Townsville Hospital, Townsville, Australia between May 2017 to December 2018. Mixed risk women with an accurately dated, singleton pregnancy underwent a pregnancy ultrasound scan at least every four weeks between 16 and 40 weeks gestation. Renal parenchymal thickness and echogenicity, renal volume, fetal growth biometries, amniotic fluid measurements, renal artery Doppler and other fetal Dopplers were assessed in appropriately grown, fetal growth restriction or large for gestational age fetuses. Results 155 participants were recruited, with 7 participants excluded due to fetal abnormalities. Mixed effects modelling was used so that variations between gestational ages within fetuses and between fetuses was considered. A reference graph was developed for normal fetal renal parenchymal growth. In growth restricted fetuses the renal parenchymal thickness was found to be significantly less when compared to the parenchymal thickness of appropriately grown fetuses. Conclusions Measurement of the renal parenchymal thickness is an innovative method to evaluate the development of the fetal kidneys. This new chart of fetal renal parenchymal thickness may be useful for the diagnosis of nephropathologies and the identification of infants at risk of kidney disease. Fetal growth restriction was found to adversely affect the renal parenchymal growth. This suggests growth restricted fetuses are born with fewer nephrons and are therefore likely to be more susceptible to hypertension and early onset kidney disease later in life.

Efficacy of the Sonoelastography Method for Diagnosis of Fibrosis in Renal Transplant Patients.

Although biopsy is the most important method for diagnosing the cause of renal allograft dysfunction, sonoelastography, a new ultrasonography method, can be used to distinguish between the soft or hard nature of lesions. In this study, our aim was to investigate whether sonoelastography could diagnose fibrosis in renal transplant patients. In this prospective study, we included patients over 18 years old who were recommended for clinical biopsy. Sonoelastographic evaluation was made by conducting acoustic radiation force impulse measurements for each patient after they were admitted to the clinic for biopsy. Measurements were performed just before the biopsy procedure. All results were examined by 2 experienced radiologists using the Siemens S3000 Ultrasound Machine (Erlangen, Germany). Comparisons of ultrasonographic values with biopsy results were made with SPSS software (SPSS: An IBM Company, version 20, IBM Corporation, Armonk, NY, USA). Of the 65 patients included in this study, pathology showed acute T-cell-mediated rejection in 37 patients. There was a significant correlation between the pathologic Banff scores and the sonographic acoustic radiation force impulse values (P = .002), where the degree of Banff increased as the mean acoustic radiation force impulse values elevated. A rise in mean impulse values correlated with increased degree of interstitial fibrosis in renal allografts. Renal parenchymal echogenicity of patients significantly differed by sex (P = .009), with an average renal echogenicity of grade 1 in women and grade 0 in men. Also, a statistically significant difference was found between age of the renal transplant recipient and resistive index values. Our study showed a significant correlation between Banff degree and the acoustic radiation force impulse values of renal transplant patients. In addition to biopsy, sonoelastography can be beneficial for the diagnosis of fibrosis in renal transplant patients.

The Relationship between Non-Renal Diseases and Renal Parenchymal Echogenicity in Children with Acute Abdominal Pain

Background Few results have shown that renal parenchymal echogenicity increases in pediatric patients with no concurrent renal diseases. This study aimed to investigate the relation between non-renal diseases and renal cortical echogenicity in children with acute abdominal pain. Materials and Methods This cross- sectional study was conducted among 100 children referred to Amirkola Children’s Hospital (Babol city, Iran) with complain of acute abdominal pain during July 2015-July 2016. Patients with a known history of renal disease or urinary tract infections were excluded. All patients were examined with sonography. The parenchymal echogenicity of kidney was evaluated by comparison with that of liver and was divided into three categories: group 1, renal cortex echogenicity less than liver parenchyma echogenicity; group 2, renal cortex echogenicity similar to that of liver parenchyma; and group 3, renal cortex echogenicity greater than that of liver parenchyma. Results: Of 93 children finally assessed, 52 (55.9%) were boy; the mean age of patients was 6.45 years old. The diagnosed causes of abdominal pain included acute appendicitis (n=43, 46.2%), mesenteric adenitis (n=8, 8.6%), gastroenteritis (n=4, 4.3%), and invagination (n=2, 2.2%). Eighteen cases (19.4%) had abnormal renal echogenicity (equal to or more than that of liver). A significant relationship was found between non-renal diseases and renal cortical hyperechogenicity (p=0.03). After follow-up of 12 patients with renal hyperechogenicity for 1-2 weeks, all of them had normal findings in re-evaluation. Conclusion The results showed that renal hyperechogenicity is a non-specific and transient finding in children with acute abdominal pain and in favor of disorders other than renal diseases.

Sonographic evaluation of renal parameters in individuals with essential hypertension and correlation with normotensives.

Hypertension can secondarily involve the kidneys, and renal sonographic parameters can be used to indirectly assess renal function or status. Ultrasound is an inexpensive and safe modality for evaluating the kidneys. The purpose of this study was to sonographically assess renal parameters in patients with essential hypertension to determine the parameters that may indicate increased risk of renal damage. One hundred and fifty individuals (96 females and 54 males) with essential hypertension attending consultant outpatient clinic in University of Benin Teaching Hospital were evaluated. An equal number of nonhypertensive volunteers comprising of 80 females and 70 males were studied as controls. For individuals and controls, the renal length, width, anteroposterior diameters, renal parenchymal volume, cortical thickness, and echogenicity were assessed. Serum creatinine was also obtained. Statistical Package for the Social Sciences (SPSS version 17.0) was used in data analysis. The mean renal parenchymal volume and cortical thickness were 99.1 ± 25.8 cm3 and 1.0 ± 0.2 cm on the right and 113.8 ± 35.8 cm3 and 1.0 ± 0.2 cm on the left for the hypertensive individuals. The values for the normotensives were 100.5 ± 19.8 cm3 and 1.2 ± 0.2 cm on the right and 118.7 ± 27.4 cm3 and 1.3 ± 0.2 cm on the left. The difference in cortical thickness between the two groups was statistically significant. No significant difference was noted between renal parenchymal volume of the right and left kidneys in the individuals and controls. The variation in cortical echogenicity between the hypertensives and controls was statistically significant; 74.0% and 75.3% of hypertensives and 28.0% and 26.0% of normotensives had increased cortical echogenicity on the right and left kidneys, respectively. The serum creatinine value was significantly higher in the hypertensive group. Cortical echogenicity grading was significantly higher among hypertensives than normotensives while renal parenchymal volume and cortical thickness were lower among hypertensives. In the hypertensives and normotensives, renal parenchymal volume, cortical thickness, and renal length were higher in males compared to the females and in the left kidney compared to the right. Hypertension seems to have more effect in the renal cortex than the medulla.

The renal parenchyma—evaluation of a novel ultrasound measurement to assess fetal renal development: protocol for an observational longitudinal study

IntroductionDisorders of fetal growth, such as intrauterine growth restriction (IUGR) and large for gestational age (LGA), have been found to have a profound effect on the development of the fetal...

Urinary tract infections in neonates with unexplained pathological indirect hyperbilirubinemia: Prevalence and significance

BackgroundIt is controversial to test for urinary tract infection (UTI) in patients with unexplained indirect hyperbilirubinemia in the first 2 weeks of life. We aimed to study the prevalence and significance of UTIs in such neonates who were requiring phototherapy. MethodsSubjects were 2- to 14-day-old neonates with indirect bilirubin levels above phototherapy limit with no other abnormality in their bilirubinaemia-related etiologic workup. UTI was diagnosed by 2 consecutive positive cultures obtained by catheterisation, documenting growth of >10,000 colonies of the same microorganism with consistent antibiograms. The UTI (+) patients were evaluated by renal ultrasonography (US), and some were followed up for possible recurrent UTI. Results262 neonates were included in the study. UTI prevalence was 12.2%, and bacteraemia was 6.2% among UTI (+) patients. The two most common pathogens (81.2%) were Escherichiacoli and Klebsiella. pneumonia. All UTI (+) patients had undergone US, revealing 12.5% pelvicaliectasis, other 12.5% increased renal parenchymal echogenicity, 3.1% concurrent pelvicaliectasis and increased renal parenchymal echogenicity. 53.1% of UTI (+) patients had undergone follow-up, after which 23.5% recurrent UTI were found at the end of a mean of 52 months. ConclusionWe suggest that the neonates with unexplained pathological jaundice should be tested for possible UTI. Consequently, all newborns with UTI shall be evaluated by the urinary US and followed up for recurrent UTI.

Increased Renal Parenchymal Echogenicity in Children with Acute Abdominal Pain: Can It Be an Alarming Sign?

Background: Ultrasound is an important imaging modality in children whit acute abdominal pain. There are many etiologies which can cause acute abdominal illness. Both kidneys are evaluated in a routine abdominal sonography. Renal echogenicity in pediatric changes with age gradually, as in neonates and early infancy we can see increased echogenicity as normal variant. But there are several studies which have stated that increased echogenicity of the renal parenchyma are an indicator of renal disease in older children and adults. On the other hand, there are a few cases of renal hyper echogenicity in children with various abdominal diseases without any renal pathologic condition. This study aimed to investigate the relationship between renal echogenicity and the final diagnosis in children with acute abdominal pain. Methods: This cross sectional study was done on 93 children referred to Amirkola Childrens hospital with complain of acute abdominal pain who were examined with sonography. Patients with a known history of renal disease or urinary tract infections were excluded. The renal parenchymal echogenicity evaluated by comparison with adjacent liver and was divided into three categories. Results: Of all 93 assessed children (52 male, 41 female) with mean age 6.45 y/o, 18 cases (19.4%) had abnormal renal parenchymal echogenicity (equal or more than liver).The final diagnosis of the cause of abdominal pain in 43 cases (46.2%) was acute appendicitis, in 8 cases (8.6%) was mesenteric adenitis, in 4 cases (4.3%) was gastroenteritis and in 2 cases (2.2%) was invagination. Conclusions: The results show that renal hyperechogenicity is nonspecific finding in children which presented with acute abdominal pain and does not necessarily an indicator of renal disease in these specific patients. According to this study, increased echogenicity of the kidneys should alert the radiologist to search the abdomen more thoroughly for a cause of the acute abdominal illness.

Correlation between Abdominal Ultrasonographic Findings and CD4 Cell Count in Adult Patients with HIV/AIDS in Jos, Nigeria

Acquired Immunodeficiency Syndrome (AIDS) is caused by Human Immunodeficiency Viruses (HIV) resulting in progressive destruction of cell mediated immunity. The abdominal manifestations of AIDS are related to the level of CD+4 cells count as well as viral load. Abdominal ultrasound examination is easy to perform, non-invasive, inexpensive, readily available and reproducible investigation which provides valuable information about abdominal findings in AIDS. The objective of the study was to evaluate abdominal ultrasound findings in adult HIV/AIDS patients in Jos, Plateau State, Nigeria and correlate these findings with the patients’ CD+4 counts. A cross-sectional study of abdominal ultrasound findings of adult patients with HIV/AIDS was conducted over a period of six months. The abdominal ultrasound findings and CD+4 counts were studied. Two hundred (40%) of the patients had normal abdominal ultrasound, while 60% (300) had various abnormalities. The common abnormalities included increased liver parenchymal echogenicity in 25.0%, hepatomegaly in 23.4%, splenomegaly in 6.6%, increased splenic echogenicity in 6.2% and thickened gallbladder wall in 12.6%, elevated renal parenchymal echogenicity in 6.4%, enlarged kidneys in 2.6%, lymphadenopathy in 6.0%, and ascites in 2.4%. Pelvic abscess was the least pathology in 0.2%. Most of the findings did not correlate with the patients’ CD+4 count except for lymphadenopathy and ascites. Although abdominal ultrasound examination is invaluable in the management of these patients, however, it has not shown to be useful in predicting the patients’ immune status.

Renal function in pediatric patients with allogeneic hematopoietic progenitor cell transplantation

Patients with hematopoietic stem cell transplantation can develop some degree of renal failure. The aim of this descriptive study is to evaluate markers of kidney injury in pediatric patients undergoing allogeneic hematopoietic stem cell transplantation between 1991 and 2011. A descriptive study of pediatric patients with allogeneic transplant of hematopoietic precursors between 1991 and 2011. The patients were between 1 month and 18 years of age at the time of the study and had at least 6 months of follow up. Clinical and nutritional history, continuous blood pressure monitoring (ABPM), urine tests, proteinuria, creatinine and renal and bladder ultrasonography imaging were evaluated. During this period 65 patients were transplanted, of which 13 patients were included. 46% (n = 6) showed diverse degrees of renal compromise defined by altered renal parenchymal echogenicity, clinic or masked hypertension and/or microalbuminuria. In this clinical group, almost half of the patients patients had some degree of renal injury in their evolution. We consider essential to assess the renal function in the follow-up of these patients.

Effect of potassium oxalate on liver function and kidney tissue of dogs (beagles)

Calcium oxalate crystalluria is a problem of growing concern in dogs. A few reports have discussed acute kidney injury by oxalates in dogs, describing ultrastructural findings in particular. We evaluated the possibility of deposition of calcium oxalate crystals in renal tissue and its probable consequences. Six dogs were intravenously injected with 0.5 M potassium oxalate (KOx) for seven consecutive days. By the end of the experiment, ultrasonography revealed a significant increase in the renal mass and renal parenchymal echogenicity. Serum creatinine and blood urea nitrogen levels were gradually increased. The histopathological features of the kidneys were assessed by both light and electron microscopy, which showed CaOx crystal deposition accompanied by morphological changes in the renal tissue of KOx injected dogs. Canine renal oxalosis provides a good model to study the biological and pathological changes induced upon damage of renal tissue by KOx injection. This article has been retracted. Link to the retraction 10.2298/ABS150615077E

Isolated pons variant of posterior reversible encephalopathy syndrome complicated with ischemic stroke in a young patient

Posterior reversible encephalopathy syndrome (PRES) is characterized by global encephalopathy, seizures, headache, or visual symptoms. Neuroimaging of PRES is typically associated with vasogenic edema in the occipital lobes and other posterior structures [1]. However, involvement of PRES in only pons is rare. The present study report a patient with isolated pons variant of PRES complicated with ischemic stroke which has not been previously reported in the literature. A 36-year-old right-handed woman was admitted to the emergency department with right-sided weakness, nausea and vomiting. She had no symptoms of headache, seizures, blurred vision or fever. She denied the history of hypertension. In admission, she was conscious with blood pressure 260/140 mmHg. Examination showed right hemiparesis (medical research council power grade 4 in the upper and the lower extremity) with extensor plantar response. The hemoglobin level was 11 g/dL and the platelet level was 145,000/mm. Her serum BUN and creatinine level were 6.15 mmol/L and 215 lmol/L, respectively. The results of serum electrolyte showed normal. The result of dynamic electrocardiogram (ECG) monitoring was normal too. The echocardiography revealed left ventricular hypertrophy. The kidney ultrasonography study exhibited a clear increase in renal parenchymal echogenicity with a poor corticomedullary differentiation. The signal in the pons and left periventricular white matter was increased in T2-weighted MRI test (Fig. 1a, b). Diffusion-weighted imaging (DWI) was normal and apparent diffusion coefficient (ADC) map showed high intensity signal in the pons (Fig. 1c, e). DWI showed hyperintense lesion corresponding to that on T2weighted images in the left periventricular white matter (Fig. 1d). The ADC map of the lesion demonstrated restricted diffusion in keeping with ischemia (Fig. 1f). Lumbar puncture and analysis of the cerebrospinal fluid were refused by her family members. She was treated with nicardipine and citicoline. Blood pressure was normalized and the patient’s weakness gradually improved within 15 days. An MRI at 18 days revealed that the pons changes were completely reversed and the lesion in the left periventricular white matter still exists (Fig. 1g, h). A diagnosis of isolated pons variant of PRES complicated with acute ischemic stroke was made and she was transferred to nephrology department. The renal biopsy revealed IgA nephropathy with proliferative sclerosing glomerulonephritis. PRES can be triggered by eclampsia, hypertensive emergency, or exposure to immunosuppression (most notably the calcineurin inhibitors) [2]. Hypertension from a renal origin has been reported to be a significant cause of PRES in one study of both pediatric and adult patients [1]. The vertebrobasilar system is relatively devoid of adrenergic sympathetic innervations, making the posterior brain regions more susceptible to overwhelm autoregulatory mechanism by acute upsurge of blood pressure [2]. Pons edema in the PRES had been reported uncommonly which H. Liang and D. Li contributed equally to this article.

Posterior Urethral Valves: Multivariate Analysis of Factors Affecting the Final Renal Outcome

Posterior urethral valves represent the most common obstructive uropathy in children with a broad spectrum of clinical severity. We evaluated prognostic variables affecting the outcome of renal function in such children. Between 1987 and 2004, 120 patients with a mean age of 2 years with posterior urethral valves were treated initially with valve ablation at our center. We studied certain parameters, including age at presentation, serum creatinine (initial and nadir), initial creatinine clearance, renal ultrasound findings (hydronephrosis and renal parenchymal echogenicity), vesicoureteral reflux on initial voiding cystourethrogram, bladder dysfunction and popoff mechanisms such as the syndrome of large vesical diverticulum, urinoma and ascites. Long-term renal outcome was assessed. Followup was 2 to 16 years (median 3.6). Renal insufficiency developed at the end of followup in 44 patients (36.5%). Serum creatinine at hospital admission, nadir serum creatinine, initial creatinine clearance and renal parenchymal echogenicity were significant predictors of the final renal outcome (p < 0.05). Patient age at diagnosis (2 or less vs greater than 2 years), upper tract dilatation, the presence or absence of vesicoureteral reflux, popoff mechanisms and bladder dysfunction had no significant impact on future renal function. On multivariate analysis nadir serum creatinine was the only independent prognostic factor. Our data confirm the high prognostic value of nadir creatinine after primary valve ablation. Also, initial serum creatinine, creatinine clearance and renal parenchymal echogenicity on initial renal ultrasound correlate significantly with long-term renal function in children with posterior urethral valves.

Disseminated cryptococcosis, an unusual cause of gross proteinuria in an HIV-infected patient.

Sir, A 52-year-old HIV-positive, ARV-naive African man was admitted with cryptococcal meningitis. Pertinent laboratory investigations included a serum creatinine of 170 mcmol/l, a urinary albumin creatinine ratio of 50 mg/mmol and urinary sodium of 268 mmol/24 h. His CD4 count was 15 cells/ml. Both hepatitis B and C serology were negative. Renal ultrasound showed normal-sized kidneys with increased renal parenchymal echogenicity suggestive of HIV-associated nephropathy. A renal biopsy, which yielded eighteen glomeruli, showed cryptococcal yeasts in some of the glomerular capillaries, tubules and within the interstitium with minimal inflammatory response. There was no evidence of collapsing glomerulopathy. The final diagnosis was cryptococcal meningitis with fungaemia and nephritis. Fig. 1 Glomerulus showing yeast forms of cryptococcocus in one of the capillary loops. Note the relatively normal background (mucicarmine ×20). Fig. 2 Mucicarmine stain highlighting the capsule of the budding yeast forms tubular lumina (×40). The patient was initially started on antifungal therapy and both his clinical state and serum creatinine improved. He was planned for highly active antiretroviral therapy as an outpatient, however, was lost to follow up on discharge.

The role of ultrasonography in the study of medical nephropathy

Diagnostic techniques in nephrology include clinical history, physical examination, laboratory tests, scintigraphy, diagnostic imaging techniques as well as renal biopsy. In kidney diseases, ultrasonography is used as a first-line imaging technique, and its role in medical nephropathy is to exclude urological pathologies, to differentiate between acute and chronic renal failure, to follow-up on the course of a disease, to guide needle biopsy, etc. Ultrasound images are useful at characterizing the pelvis, assessing renal dimensions and parenchymal echogenicity, sampling color–power Doppler signals and evaluating their characteristics and distribution as well as measuring parenchymal resistive index. Taken together, these data can provide useful clues to the diagnosis and help to reduce the number of possible differential diagnoses.

Increased Echogenicity as a Predictor of Poor Renal Function in Children With Grade 3 to 4 Hydronephrosis

Prenatally diagnosed hydronephrosis is a common finding that often requires further radiological evaluation to determine whether it is associated with compromised renal function. We hypothesize that findings on postnatal renal sonography may help determine which patients require more extensive evaluation of renal function in the assessment for prenatal hydronephrosis. We show that increased renal parenchymal echogenicity on postnatal US is a strong predictor of compromised renal function. A total of 97 patients diagnosed with prenatal hydronephrosis presented to our institution for furosemide (99m)technetium MAG3 renogram evaluation of renal function between January 2000 and December 2001. All patients had SFU grade 3 to 4 hydronephrosis noted on postnatal US before age 6 months. For these 97 patients (178 renal units) we correlated the degree of renal parenchymal echogenicity and parenchymal thinning on the first postnatal sonogram with the differential renal function as determined by furosemide MAG3 renography. Among 97 patients diagnosed with prenatal hydronephrosis 10 of 20 renal units (50%) with markedly increased echogenicity had severely decreased relative renal function of less than 10%, while 136 of 151 (90%) with normal echogenicity exhibited normal relative renal function of 40% or greater. Increased echogenicity on US yielded a sensitivity of 100% and specificity of 99% for predicting relative renal function of 20% or greater. In predicting relative renal function of 40% or less sensitivity and specificity were 48% and 100%, respectively. Increased renal parenchymal echogenicity found on the first postnatal ultrasound can be used as a predictor of impaired relative renal function as measured on furosemide MAG3 renogram.

Autosomal recessive polycystic kidney disease: radiologic-pathologic correlation.

Autosomal recessive polycystic kidney disease is a heritable but phenotypically variable disorder characterized by varying degrees of nonobstructive renal collecting duct ectasia, hepatic biliary duct ectasia and malformation, and fibrosis of both liver and kidneys. In the kidney, the dilated collecting ducts and interstitial fibrosis, when severe, may significantly impair renal function and result in hypertension and renal failure. Imaging typically shows large but reniform kidneys, diffusely increased renal parenchymal echogenicity at ultrasonography, and a striated nephrogram after contrast material administration. In the liver, periportal fibrosis accompanies the malformed and dilated bile ducts; this may result in portal hypertension. The liver may appear normal or may show intrahepatic biliary dilatation; once portal hypertension develops, splenomegaly and varices are usually evident. The relative degrees of kidney and liver involvement tend to be inverse: Children with severe renal disease usually have milder hepatic disease, and those with severe hepatic disease tend to evidence mild renal impairment. Presently, treatment consists of supportive management and control of hypertension. Replacement therapy for renal failure (dialysis or kidney transplantation) and control of portal hypertension (portal circulatory diversion or liver transplantation) may be necessary.

Prenatally Diagnosed Bilateral Hyperechoic Kidneys With Normal Amniotic Fluid: Postnatal Outcome

We evaluated a subset of infants with bilateral markedly hyperechoic "bright" kidneys noted prenatally in association with normal amniotic fluid volume during gestation. Prenatal ultrasound showed increased renal parenchymal echogenicity bilaterally with preservation of the medullary pyramid architecture. These children were followed for up to 3 years to determine potential changes in the sonographic appearance of the echogenic renal parenchyma and to assess renal function. In 3 years 8 cases of bilateral hyperechoic fetal kidneys were identified. During postnatal followup renal echogenicity resolved in 4 cases, diminished in 1 and remained the same in 3. The serum creatinine and electrolytes were normal in all cases followed for more than 3 months. Other renal findings included vesicoureteral reflux in 2 of 7 cases, mild pelvic ectasia in 1 and tiny medullary calcifications in 1. The specific etiology of increased echogenicity is unknown, although 1 infant appeared to have a form of autosomal recessive disease with liver hyperechogenicity as well. We conclude that fetuses with bilateral hyperechoic kidneys associated with normal amniotic fluid volume have a favorable outcome. Ultrasonographic finding of marked parenchymal hyperechogenicity appears to improve with time; in our experience renal function is normal and the infants thrive. Continued followup is necessary to determine the long-term natural history of this phenomenon, as is subsequent prenatal and postnatal evaluation of future siblings to assess genetic risk.

Ultrasonographic imaging and doppler analysis of renal changes in non-insulin-dependent diabetes mellitus

We used ultrasonographic imaging and Doppler analysis to assess renal changes in patients with non-insulin-dependent diabetes mellitus (NIDDM) and normal renal function, as established by normal serum creatinine levels and the absence of macroalbuminuria. Renal parenchymal echogenicity, renal volume, and resistive index (RI) were blindly evaluated for 85 NIDDM patients and 42 age-matched control subjects (C). Results were analyzed and correlated with the following clinical parameters: patient age, duration of diabetes, blood pressure, blood glucose and cholesterol levels, and the presence of microalbuminuria. Normal renal parenchymal echogenicity was seen in all but one NIDDM patient; however, in comparison with C, diabetic patients had significantly higher renal volume (mean +/- standard deviation, 314.01 +/- 72.74 vs 227.64 +/- 58.76) and RI (mean +/- standard deviation, 0.71 +/- 0.05 vs 0.64 +/- 0.02). An RI higher than 0.70 was found in 55 of 85 (65%) NIDDM patients; an increased RI was directly correlated with patient age, whereas an inverse correlation existed between an increased RI and renal volume. No statistically significant differences were observed for the duration of diabetes, arterial hypertension, blood levels of glucose and cholesterol, and the presence of microalbuminuria. NIDDM patients with normal renal function show a significant increase in renal volume and RI in comparison with C. Demonstration of these findings may aid in the detection of early renal involvement in NIDDM patients. However, further investigations are needed to understand fully the correlation of such changes with the pathology of diabetic nephropathy and to provide an interpretation of the pathophysiologic mechanisms underlying changes in intrarenal vascular impedance in NIDDM patients.

Increased renal parenchymal echogenicity in the fetus: importance and clinical outcome.

Pre- and postnatal ultrasound (US) findings and clinical course in 19 fetuses (16-40 menstrual weeks) with hyperechoic kidneys (renal echogenicity greater than that of liver) and no other abnormalities detected with US were evaluated to determine whether increased renal parenchymal echogenicity in the fetus indicates renal disease. Four infants (21%) were healthy at birth and had normal postnatal sonograms. Another 10 infants (53%) survived, but abnormalities were found at neonatal US. Postnatal diagnoses in these 10 neonates included unilateral renal dysplasia (n = 3), unilateral multicystic dysplastic kidney and a contralateral hyperechoic kidney (n = 2), hydronephrosis (n = 2), and renal abnormalities of unknown type (n = 3). Five fetuses with either infantile polycystic kidney disease (n = 4) or bilateral multicystic dysplasia (n = 1) did not survive. Oligohydramnios was predictive of a poor prognosis. Hyperechoic renal parenchyma in the fetus was associated with sonographic or functional abnormalities in 15 of 19 cases (79%) and a 74% survival rate.

Densitometric measurement of renal echogenicity in infants and naked eye evaluation: A comparison

The sonograms of 115 infants with normal renal function ranging in age from 1 to 120 days used to determine renal parenchymal echogenicity by densitometry. The measured values were contrasted with the evaluations of 4 independent examiners who rated renal echogenicity as "less than", "equal to" or "greater than" that of the liver. The results revealed that naked eye evaluation does not permit a clear distinction between the categories of echogenicity and also that the assessments of the individual examiners differed considerably. Contrary to the previously held view the present findings indicate that the initially increased renal parenchymal echogenicity in neonates has developed into the normal hypoechoic condition after 1 month. One should take these findings into account when evaluating renal sonograms of infants, especially if no densitometric data are available.