Transient and reversible nephrotoxicity of sarin in rats

Organophosphate (OP) poisoning, which inhibits cholinesterase activity, leads to severe cholinergic symptoms. Effective and quick management of these symptoms is considered critical to the clinical outcome. Acute renal damage following exposure to OP insecticides has been reported. Similar complications might occur following exposure to OP nerve agents, however, this subject has been studied only sporadically. In the present study, the effect of the nerve agent sarin on renal function was examined in rats. A single dose of sarin ( approximately 0.9 LD(50)) led to a significant reduction (of 45%) in renal function during the first 2 days post exposure, as exhibited by evaluation of the glomerular filtration rate, through measuring the clearance of ( 99m)Tc-DTPA. The urine volume was reduced by 50%, the urine specific gravity increased to 104% of the control value and massive hematuria and glucosuria were recorded 24-48 h post exposure. In addition, around 60% decrease in urine electrolytes was monitored during the first 2 days following exposure, with a recovery after 8 days. Post mortem gross inspection of the bladder, 24 h post exposure, revealed severe edema and hemorrhage. Treatment with the muscarinic antagonist atropine and the oxime TMB-4, at excessive doses administered 1 min post exposure, did not prevent most renal impairments. It has been concluded that sarin caused an acute renal dysfunction, possibly accompanied by bladder damage. These impairments were reversible, recovered spontaneously within 3-8 days, and were probably related to the state of shock and hypovolemia caused by the poisoning. However, if renal impairments are left unattended, they might contribute to the overall toxic manifestation and as a result aggravate the clinical state of intoxicated casualties.

Factors that determine an incomplete recovery of renal function in macrohematuria-induced acute renal failure of IgA nephropathy

Acute renal failure that is associated with macroscopic hematuria (ARF-MH) is a widely known complication of IgA nephropathy (IgAN). Although spontaneous recovery of renal function after cessation of MH has been described, no long-term outcome studies have been performed. The outcome of patients who had biopsy-proven IgAN and presented an ARF-MH episode in the period 1975 through 2005 was studied. Thirty-six episodes of ARF-MH that occurred in 32 patients were identified. A complete recovery of baseline renal function after cessation of MH was observed in 27 (group 1); in the remaining nine episodes (25%; group 2), estimated GFR (eGFR) did not reach the baseline value. Final eGFR was 89 +/- 28 ml/min per 1.73 m(2) in group 1 patients and 38 +/- 12 ml/min per 1.73 m(2) in group 2 patients (P = 0.0005). The duration of MH was significantly longer in group 2 patients: 33.7 +/- 25.3 versus 15.4 +/- 18.4 d (P = 0008). A high proportion of tubules that were filled by red blood cell casts and had signs of acute tubular necrosis were the most striking histologic abnormalities. In conclusion, a significant proportion (25%) of ARF-MH in IgAN did not recover the baseline renal function after the disappearance of MH. Duration of MH longer than 10 d, age >50 yr, decreased baseline eGFR, absence of previous episodes of MH, and the severity of tubular necrosis were significant risk factors for an incomplete recovery of renal function.

Retrograde proximal rigid ureteroscopy and pyeloscopy in prepubertal children: safe and effective

PURPOSE

Traditionally, rigid ureteroscopy in adults has been reserved for distal ureteral procedures, due to the risk of injury associated with proximal ureteroscopy. However, the safety of proximal rigid ureteroscopy in prepubertal children is not well established.

MATERIALS AND METHODS

We retrospectively evaluated all prepubertal children (12 years old and younger) who underwent attempted rigid proximal ureteroscopy and pyeloscopy. The indications for ureteroscopy were treatment of ureteral and/or renal pelvic calculi, and evaluation of hematuria. All patients were evaluated postoperatively with renal and bladder ultrasonography and abdominal radiography (if stone was visible before treatment).

RESULTS

A total of 24 consecutive children 3.4 to 12 years old underwent 24 ureteropyeloscopic procedures. Of these children 20 (83%) successfully underwent 20 rigid ureteroscopic and pyeloscopic procedures. However, 4 procedures (17%) were converted from rigid to flexible endoscopy to perform 4 successful ureteropyeloscopies. The indications for ureteroscopy were treatment of ureteral and/or renal pelvic calculi in 22 patients and evaluation of hematuria in 2. Followup was 0.6 to 3.6 years (mean 1.9) for the patients undergoing rigid ureteropyeloscopy. All children with calculi were rendered stone-free based on direct visualization by complete ureteroscopy and pyeloscopy of the affected system. No complications occurred during any of the procedures.

CONCLUSIONS

Proximal rigid ureteroscopy and pyeloscopy can be safely applied toward treatment of proximal ureteral and renal pelvic calculi as well as diagnostic ureteropyeloscopy in prepubertal children. The technique has several advantages compared to flexible ureteroscopy.

Genitourinary tuberculosis in a medical center in southern Taiwan: an eleven-year experience

BACKGROUND AND PURPOSE

Genitourinary tuberculosis is the second most common disease form of extrapulmonary tuberculosis. This study analyzed the clinical characteristics and outcome in 31 patients with genitourinary tuberculosis treated between 1994 and 2004 at a tertiary medical center in southern Taiwan.

METHODS

Data were collected by chart review. Diagnosis was based on microbiological or histological proof plus compatible radiographic findings and clinical presentation.

RESULTS

This study included 14 men (45%) and 17 women (55%). Their ages ranged from 31 to 81 years (mean, 58.1 years). Genitourinary symptoms (83.9%) were more frequent than constitutional symptoms (35.5%). Pyuria plus hematuria with sterile culture (51.6%) was the most common finding. Only 25.8% of patients had a known history of pulmonary tuberculosis. Diagnosis was based on microbiological findings in 11 patients (35.5%), and by histological findings in 20 (64.5%) patients. Intravenous pyelography revealed abnormalities in 94% of patients and renal ultrasonography in 79.2%. Imaging studies were characteristic of advanced stage in most patients. Twenty-five percent of patients were classified as having treatment failure after at least 6 months of therapy. The treatment failure rate was higher in patients with positive microbiological findings (71.4%) than in those with histological findings alone (5.9%, p=0.003).

CONCLUSIONS

The high rate of treatment failure and advanced stage of disease at diagnosis are indicative of the challenge in the care of patients with genitourinary tuberculosis in Taiwan.

The renal allograft donor with isolated microhematuria

Recently, there has been extensive debate about extending the criteria for accepting living donors to include the presence of mild renal abnormalities such as isolated microhematuria. Hematuria defined as the detection of greater than five red blood cells per high power field can be associated with abnormalities throughout the urinary tract. Detection of casts or dysmorphic red blood cells in the urine sediment with or without proteinuria could indicate underlying intrinsic renal disease. Anatomic causes, such as stones and tumors, should be excluded; cystoscopy may be indicated to exclude bladder pathology. Obviously, urinary tract infection, uncontrolled hypertension and latent diabetes mellitus must be excluded. Microscopic hematuria could be associated with mesangial IgA deposits; as 10% of first-degree relatives of patients with IgA glomerulonephritis suffer from microhematuria and/or proteinuria that may require consideration of renal biopsy. Microhematuria could also be associated with other known hereditary renal diseases such as C3 deposits disease, IgM nephropathy, autosomal dominant polycystic kidney disease, Alport's syndrome or thin basement membrane disease. In conclusion, careful assessment of isolated microhematuria, in the context of living kidney donation, is mandatory as results may reveal occult renal disease that may contraindicate kidney donation.

False positive dipstick for urinary blood in childhood

BACKGROUND

In view of the obvious practical advantages, the most common test for hematuria is currently a reagent strip.

METHODS

A standardized microscopic examination of the sediment was performed in 20 asymptomatic children referred for evaluation of chronic isolated microhematuria detected by means of a reagent strip.

RESULTS

In 6 of the 20 children the microscopic examination failed to confirm the result of the dipstick test.

CONCLUSIONS

Confirmation for the presence of hematuria by microscopy is the most important step in children with a positive dipstick for urinary blood.

Analysis of renal biopsies performed in children with abnormal findings in urinary mass screening

BACKGROUND

School urinary mass screening tests are performed to make early diagnosis and provide proper treatment for chronic renal diseases. However, very few systemic analyses or studies have been reported regarding final diagnosis made on children with abnormal urinary screening results.

AIM

To study the cases of renal biopsy in children detected in urinary screening.

METHODS

We retrospectively analysed 461 cases of renal biopsy performed on children referred to us with abnormal school urinary mass screening results who satisfied indications for renal biopsy.

RESULTS

Pathologically abnormal findings were observed in 285 (61.8%) patients. Thin glomerular basement membrane disease was detected in 127 (27.5%) cases and IgA nephropathy in 121 (26.2%) cases. Among those 461 children, microscopic haematuria was observed in 289 (62.7%) patients, proteinuria in nine (2.0%), and both in 163 (35.4%). In addition, a statistically higher rate of pathological abnormalities on renal biopsy was noted in the group with microscopic haematuria combined with proteinuria and also in cases with more severe haematuria.

CONCLUSION

School urinary mass screening has greatly contributed to diagnosing chronic renal diseases. Continuous medical observation is required when abnormal urinalysis is observed, and a more aggressive medical approach such as renal biopsy should also be performed if necessary.

Thin glomerular basement membrane nephropathy: incidence in 3471 consecutive renal biopsies examined by electron microscopy

CONTEXT

Thin glomerular basement membrane (GBM) nephropathy is often equated with benign familial hematuria, although it may occur sporadically and may not always be benign. Thin GBM nephropathy is reported to occur in at least 1% of the population, although its reported incidence varies considerably in different studies because there are presently no uniform criteria for its diagnosis by electron microscopy (EM).

OBJECTIVE

To determine the incidence of thin GBM nephropathy in a large sample of renal biopsies using a basic methodology that can easily be applied in any diagnostic EM laboratory.

DESIGN

Direct measurements of GBM thickness were made from electron micrographs at 3 specified points along each of 10 randomly selected glomerular capillaries to determine an average GBM thickness for each of 50 males and 50 females, ages 9 to 80 years, with minimal-change nephropathy or acute interstitial nephritis, without hematuria. The means of the average GBM thickness values were 330 +/- 50 (SD) nm in the males and 305 +/- 45 nm in the females; normal ranges for each sex were defined as being within 2 SD of these means. The average GBM thickness was then similarly determined for renal biopsies with suspected thin GBMs examined from January 2000 to December 2004; a total of 3471 renal biopsies were examined by EM during this period.

SETTING

Academic medical center renal pathology/EM laboratory.

RESULTS

Excluding biopsies with immunoglobulin A nephropathy, which is known to be frequently associated with thin GBMs, and biopsies with Alport syndrome, 67 biopsies (1.9% of total) had an average GBM thickness below the sex-specific normal range. Of these, 37 biopsies were performed specifically because of hematuria and had an average GBM thickness of 121 to 215 nm (mean, 185 +/- 20 nm). The remaining 30 (0.9%) biopsies, with average GBM thicknesses of 143 to 227 nm (mean, 190 +/- 20 nm), represent cases of incidentally discovered thin GBM nephropathy.

CONCLUSIONS

Based on the frequency of incidentally discovered cases and taking into account excluded cases and biopsies (eg, with diabetic nephropathy) in which diagnosis of incidental thin GBM nephropathy by EM is not possible, the incidence of thin GBM nephropathy in our population is estimated to be between 1% and 2%. Diseases most often associated with incidental thin GBM nephropathy were focal segmental glomerulosclerosis (10 cases) and minimal-change nephropathy (5 cases).

Urinary Bladder Lesions in Bovine Enzootic Haematuria

In cattle, bracken fern chronic toxicity is characterized by the presence of multiple tumours in the bladder (bovine enzootic haematuria). From October 1999 to March 2003, 433 urinary bladders with macroscopical lesions were collected in the slaughterhouse of São Miguel Island (Azores, Portugal), an endemic area where Pteridium aquilinum infestation in pastures is high. Bladder lesions were divided into three main categories (inflammatory lesions, non-neoplastic epithelial abnormalities and tumours) and described in detail. In some cases, neoplastic growth was confined to a single site, but in most cases multiple tumours developed within the same bladder. Epithelial tumours alone were present in 51.2% of the affected bladders, mesenchymal tumours alone in 17.4%, and both epithelial and mesenchymal tumours in the remaining 31.4%. The large number of tumours examined (870) revealed new categories not yet included in other veterinary classification systems, namely, inverted papilloma, papillary neoplasm of apparent low malignant potential, and haemangioendothelioma.

A case of amelogenesis imperfecta, cleft lip and palate and polycystic kidney disease

OBJECTIVE

Amelogenesis imperfecta (AI) is a heterogeneous group of genetic disorders characterized by developmental abnormalities of tooth enamel. The AI is also seen as part of multi-organ abnormalities, e.g. with cone-rod dystrophy, hypothalamo-hypophyseal insufficiency and renal failure. The present patient with AI and nephrocalcinosis exhibited a phenotype different from previous cases with renal failure. To highlight the characteristics of this rare case, extensive analysis that included histological, biochemical and genetic examinations was performed.

PATIENT

The present Japanese male patient exhibited dentition with AI and bilateral cleft lip and palate. Ground sections of his extracted tooth showed that it was hypomaturation-type AI, unlike previous cases with nephrocalcinosis were hypoplastic-type. He showed nephrocalcinosis and hematuria at 15 years of age but these symptoms appeared to be secondary to polycystic kidney disease. He showed skeletal Class II pattern with a retrognathic profile and retroclined incisors of both arches. A dolicofacial appearance was seen with an enlarged gonial angle. Biochemical makers including serum alkaline phosphatase, parathyroid hormone, calcitonin, calcium, and phosphate, were all in the normal range. Sequence analysis of the genes encoding amelogenin and enamelin, which are known to be responsible for hypoplastic-type AI, did not reveal any mutations. Since mouse null mutant of homeobox transcription factor, Msx2, exhibits a phenotype resembling AI, the human homolog of this gene, MSX2, was sequenced. There was a missense mutation of T447C that resulted in the conversion of methionine to threonine at 129.

Clinicopathological features and the prognosis of IgA nephropathy in Japanese children on long-term observation

AIMS

Clinicopathological features were investigated to clarify the ultimate prognosis and prognostic indicators for patients with IgA nephropathy in Japanese children.

METHODS

We evaluated the outcomes of 181 patients in whom IgA nephropathy was diagnosed before the age of 15 years since September 1979 and followed-up at least for three years with regard to clinical data at the onset of symptoms and renal histologic data.

RESULTS

After mean follow-up of 7.3 years from onset, 91 patients of 181 (50.3%) were in clinical remission at the last examination, 24 (13.2%) had isolated hematuria, 59 (32.6%) had hematuria and proteinuria. Eighteen of 59 (9.9%) had proteinuria more than 1 g per 24 hours. Hypertension was observed in 12 cases and 7 (3.9%) developed end-stage renal disease. Except 7, no patient had reduced renal function and elevated serum creatinine at the final follow-up. Predicted renal survival rate from onset was 92.3% at 10 years and 89.1% at 20 years. In multivariable analysis, age at onset and chronic changes of tubulointerstitium were associated with poor outcome.

CONCLUSIONS

Of 181 children with IgA nephropathy, 50% regressed, remaining 46% had hematuria and/or proteinuria and 4% of patients lapsed into end-stage renal disease. Our results indicate that childhood IgA nephropathy has a benign course and the risk for end-stage renal disease is lower than that of adults. Age at onset and tubulointerstitial lesions were the strong predictors of a progressive course of childhood IgA nephropathy.

A useful new classification of dysmorphic urinary erythrocytes

BACKGROUND

Among dysmorphic urinary erythrocytes (D cells), G1 cells or doughnut-shaped erythrocytes with one or more blebs are considered to be reliable markers for glomerular diseases. However, although there are many D cells with cytoplasmic color loss and without blebs in the urinary sediment, the significance of these cells is not clear. In this study, we devised a classification system for D cells and examined the relation between these cell types and urinalysis data.

METHODS

We classified D cells into three types (D1, D2, and D3 cells): D1 cells showed a ring-like shape and severe loss of cytoplasmic color with protrusions or blebs; D2 cells showed a doughnut-like shape and moderate cytoplasmic color loss with protrusions or blebs; and D3 cells showed a doughnut-like shape and mild cytoplasmic color loss without protrusions or blebs. We calculated the numbers of D cells of each type in 45 patients with glomerular diseases and in 303 general outpatients. This was done by bright-field microscopy modified for the analysis of urinary sediment, and we also examined the significance of these cell types.

RESULTS

In the 45 patients with glomerular diseases, the numbers of D1, D2, and D3 cells correlated with urine levels of proteinuria and hematuria and numbers of cellular and fatty casts. Numbers of D1 and D2 cells correlated with urine concentrations of albumin and N-acetyl-beta-D-glucosaminidase, and the proportions of D1 and D2 cells in D cells increased with the activity of glomerular diseases classified by urinalysis data. Only the number of D1 cells correlated with the urine concentration of potassium, which may increase in hemolysis. In the 303 outpatients, the sensitivity of D3 cells and D1 and/or D2 cells (G1 cells) was 73% and 46%, respectively, for the detection of glomerular diseases and the specificity was 93% and 99%, respectively.

CONCLUSIONS

These data indicate that the D3 cell is a sensitive marker for glomerular diseases, and that D1 and/or D2 cells are markers for severe glomerular diseases.

Glomerular basement membrane thickness in normal adults and its application to the diagnosis of thin basement membrane disease: an Indian study

Microscopic hematuria of non-urologic origin warrants ultrastructural study of renal biopsy. Thinning and variations in the texture of glomerular basement membrane (GBM) are difficult to be recognized under light microscope; transmission electron microscope (TEM) therefore plays a vital role in identifying such changes. Ultrastructural morphometry is a valuable diagnostic aid when GBM is suspected of being abnormally thin. In an effort to determine the normal GBM thickness (GBMT) in Indian adults and to determine the cutoff value of GBMT for a diagnosis of thin basement membrane disease (TBMD), we determined GBM thickness in 25 normal adults. Postmortem biopsies of 25 normal adults (16 males and 9 females) aging between 18-58 years were included in the study. GBM thickness was determined through ultrastructural morphometry on accurately enlarged electron micrographs as harmonic mean of 50 orthogonal intercepts across the GBM in each case. Study revealed a mean GBM thickness of 321 nm with a standard deviation (SD) of 28 nm. Mean-2SD (321-56), that is 265 nm, was fixed as cutoff value of GBMT for the diagnosis of TBMD. A systematic split study of control subjects revealed thicker GBM (329+/-38 nm) in higher age group (35-60 years) as compared to GBMT (316+/-21 nm) in lower age group (18-30 years). Males in higher age group also revealed thicker GBM (males: 343+/-39 nm versus females: 300+/-12 nm). Ten patients with non-urologic hematuria and having GBMT<265 nm were diagnosed as cases of TBMD. Patients with TBMD revealed significantly attenuated GBM as compared to age and sex matched controls (214 +/- 40 nm versus 311 +/- 17 nm; p<0.0005). No overlap was observed in the distribution of GBMT in patients of TBMD and age and sex matched controls. Ultrastructural morphometry is the ultimate and appropriate method for diagnosing TBMD.

[Virtual multislice computed tomography cystoscopy for evaluation of urinary bladder lesions]

The introduction of multislice computed tomography (MDCT) with the possibility of acquiring isotropic datasets has been an ideal prerequisite for development of virtual MDCT cystoscopy. Remarkable technical progress regarding post-processing of high-resolution 3D datasets as well as a considerable reduction of the time required for post-processing made it possible to introduce virtual MDCT cystoscopy into the clinical routine. 3D post-processing that often required 7-8 h when virtual endoscopy techniques were first developed can now be performed in less than 5 min after transfer of data to the 3D workstation. With the limitations and contraindications of conventional cystoscopy in mind, virtual MDCT cystoscopy may be seen as a valuable alternative to conventional cystoscopy for evaluation of hematuria.

Childhood thin GBM disease: review of 22 children with family studies and long-term follow-up

Thin glomerular basement membrane (GBM) disease is generally known to have a good renal prognosis, although renal insufficiency has sometimes been reported and the overlap with Alport syndrome implies that a good prognosis cannot be guaranteed. In order to shed light on long-term prognosis of thin GBM disease we have retrospectively evaluated 22 children with persistent haematuria and biopsy-proven thin GBM. Mean follow up was 7 years (range 2-17 years), mean age at onset was 7 years (range 1.5-15). Biopsies were performed a mean of 3.8 years after detection of hematuria. The light microscopy (LM) and immunofluorescence (IF) findings were essentially unremarkable in all of the children, while electron microscopy (EM) showed thinning of the GBM in all cases and no changes characteristic of Alport syndrome. The family history was positive for renal disease in 17 (77.3%) patients with hematuria in 8 (36.3%) families, and hematuria with renal failure (RF) or deafness in 9 (40.9%). It was completely negative for renal disease in 4 (18.2%) and unavailable in 1 (4.5%). Four patients (18%) showed a decline in renal function after 6, 8, 9 and 12 years of follow-up, and 1 of these also developed hearing impairment. None developed hypertension. Our study suggests that thin GBM disease is not always benign and a child with thin GBM should never be assigned such a prognosis, especially if there is a family history of renal impairment or deafness, where careful follow-up is needed due to the risk of late onset renal failure.

[Study on the relationship between blood stasis syndrome and clinical pathology in patients with IgA nephropathy]

OBJECTIVE

To explore the relationship between blood stasis Syndrome and clinical pathological parameters in patients with IgA nephropathy (IgAN).

METHODS

The clinicopathological data were analyzed of 94 IgAN patients of traditional Chinese medicine blood stasis syndrome.

RESULTS

Of the 94 IgAN patients, 61.70% had blood stasis syndrome (BS) and 38.30% had non- blood stasis syndrome (non-BS). In patients with BS, dark purple tongue proper was the symptom most commonly seen; the clinical manifestations were mostly proteinuria with hematuria, often accompanied with hypertension and renal dysfunction. Compared with those in patients without BS, plasma levels of serum creatinine (SCr), triglyceride (TG) and plasma fibrinogen (FIB) were obviously higher, activated partial thromboplastin time (APTT), and urokinase-type plasminogen activators (u-PA) significantly lower; and scores of glomerular sclerosis, tubular interstitial lesions, interstitial inflammatory cell infiltration, interstitial fibrosis, tubular atrophy and vascular sclerosis significantly higher. Besides, the Lee's grades in them of III - V were mostly seen.

CONCLUSION

Blood stasis syndrome of IgAN are correlated with certain clinical parameters and severity of renal pathological changes. The combination of TCM holistic syndrome differentiation and modern medicinal micro-differentiation is more favorable for making clear the nature of blood stasis Syndrome of IgAN.

Hematuria and proteinuria in a mass school urine screening test

A total of 1,044 school children identified with hematuria and/or proteinuria during a mass school urine screening test were referred to pediatric nephrologists at 13 hospitals in Korea. These children had isolated hematuria (IH) (60.1%), isolated proteinuria (IP) (26.4%: transient, 19.6%; orthostatic, 4.9%; persistent, 1.9%) or combined hematuria and proteinuria (CHP) (13.5%). The patient's history, physical examination, laboratory tests, kidney ultrasound and Doppler ultrasonography were obtained. Renal biopsies were performed on 113 children who showed severe proteinuria, hypertension, abnormal renal function, family history of chronic renal disease, systemic diseases or persistent hematuria and/or proteinuria for more than 12 months. IgA nephropathy (IgAN), thin basement membrane nephropathy (TBMN), membranoproliferative glomerulonephritis (MPGN), focal segmental glomerulosclerosis (FSGS), other GN, Alport syndrome and lupus nephritis were detected. IgAN and TBMN were the most common causes in the CHP group and IH group, respectively. Abnormal findings on the renal ultrasound with or without Doppler ultrasonography were noted in 147 cases (suspected nutcracker phenomenon, 65; increased parenchymal echogenicity, 40; hydronephrosis, 15). This study showed that the use of a mass school urine screening program can detect chronic renal disease in its early stage and recommends that more attention should be paid to identifying those children with CHP and massive proteinuria. A school urine screening program can detect chronic renal disease in its early stage. When mass screening is used, the initial aggressive diagnostic procedures such as renal biopsy are not needed. In addition, a regular follow-up for those children with IH and IP is certainly warranted.

Value of urinary excretion of microalbumin in predicting glomerular lesions in children with isolated microscopic hematuria

Urinary microalbumin excretion was assessed in 76 children with asymptomatic microscopic hematuria in whom the presence of proteinuria, hypertension, reduced renal function, hypercalciuria, urinary tract infection or structural abnormality of the urinary tract had been excluded. All children underwent a percutaneous kidney biopsy to determine whether microalbumin excretion can be used as a marker to predict the source of hematuria. Microalbumin excretion was considered normal if the urinary ratio of microalbumin to creatinine (MA/Cr ug/mg) was < or =30. Twenty-two (29%) had microalbuminuria (MA/Cr 96+/-30 microg/mg) and 54 (71%) had normal albumin excretion (MA/Cr 13+/-2 microg/mg). Of those with normoalbuminuria, 38 (70%) had normal renal tissue, 15 (28%) thin glomerular basement membrane (TGBM) disease and 1 (2%) IgA nephropathy. In contrast, 20 (91%) of those with microalbuminuria had IgA nephropathy and 2 (9%) had TGBM disease. The mean urinary MA/Cr ratio for all IgA children was 89+/-32 microg/mg higher compared with a value for the children with TGBM disease (14 +/-3 microg/mg, P <0.001) or children whose renal biopsy appeared normal (11+/-2 microg/mg, P <0.001). Statistical analysis revealed no significant differences between the mean MA/Cr ug/mg ratio for children with TGBM disease and those with normal glomerular findings. Fourteen of the 20 children with IgA nephropathy who also had microalbuminuria were treated with an angiotensin-converting enzyme (ACE) inhibitor. Over a mean follow-up of 51 months, none developed overt proteinuia; hematuria resolved and microalbuminuria returned to normal in eight (57%) during therapy with the ACE-inhibitor. In contrast, hematuria persisted and prtoteinuria developed in the other untreated children. None of the children with TGBM disease developed overt proteinuria after a mean of 51 months. Hematuria was persistent in children with TGBM disease, but often resolved in those whose biopsies were completely normal. These data suggest that determination of urinary microalbumin excretion is warranted in the routine examination of children with isolated microscopic hematuria. Routine screening for microalbuminuria may help to identify a subgroup of patients with IgA nephropathy who are at high risk for progressive kidney disease and need more intensive therapy and closer follow-up.

Hematuria in Thin Basement Membrane Nephropathy

Thin basement membrane nephropathy (TBMN) often is diagnosed clinically when there is persistent dysmorphic or glomerular hematuria, but minimal proteinuria, normal kidney function, and no other obvious cause. This study investigated hematuria in patients with TBMN. A total of 112 patients with biopsy examination-proven TBMN were studied. All had hematuria at the time of presentation, with a mean urinary red blood cell (RBC) count of 256 +/- 250 x 10 3 /mL. Seventy-five (67%) patients attended for review over a median of 48 months (range, 3-120 mo) and provided a total of 485 urine specimens. Twenty-one patients (28%) had no hematuria by phase-contrast microscopy on at least 1 occasion. These corresponded to 32 urine specimens (7% of total). Of the 21 patients, the most recent urinary RBC counts were within the normal range in 11 (52%), but hematuria had recurred in the other 10 (48%). Hematuria is persistent in most patients with TBMN, but occasionally it resolves or is intermittent.

A case of a solid renal mass together with a cystic pancreatic lesion in a 50-year-old patient

CONTEXT

Pancreatic cysts may be incidentally detected in asymptomatic patients evaluated for other clinical manifestations. Microcystic adenomas are particularly rare among pancreatic cyst neoplasms. They are benign lesions and can present as solitary pancreatic tumors or as a radiological manifestation combined with other cystic and tumoral lesions affecting different organs.

CASE REPORT

A 50-year-old man presented with hematuria. A computed tomography scan of the abdomen showed a 9-centimeter renal mass in the left kidney consistent with a renal-cell carcinoma as well as a cystic lesion the head of the pancreas. The histopathological study of the cystic mass, following a computed tomography guided biopsy, showed a microcystic adenoma. Therefore, further studies were performed so as to assess the relationship between both lesions and determine the final diagnosis.

CONCLUSIONS

Microcystic adenomas are exceedingly rare tumors among pancreatic cysts. The combination of a solid renal mass and a pancreatic cystic lesion should lead to a broad differential diagnosis. Pancreatic magnetic resonance imaging has been proven to be particularly useful in evaluating cystic masses. The presence of walls and internal septations in the pancreatic mass with gadolinium enhancement should raise the possibility of an underlying Von Hippel-Lindau syndrome.

Thin glomerular basement membrane disease: clinical significance of a morphological diagnosis--a collaborative study of the Italian Renal Immunopathology Group

BACKGROUND

Thin glomerular basement membrane disease (TBMD) is a nephropathy defined by diffuse thinning of the glomerular basement membrane (GBM) at electron microscopy examination, without the alterations of Alport's syndrome (ATS). It is known that many patients with TBMD have a type IV collagen disorder and that the disease occasionally may be progressive. This study investigated 51 patients with the morphological diagnosis of TBMD lacking any sign of ATS, with the aim of defining the prevalence of type IV collagen mutations and the course of the disease.

METHODS

Patients were investigated as follows: (a) clinical picture and family investigation; (b) renal biopsy findings; (c) immunohistochemical study of renal tissue for collagen IV alpha-chains; (d) pedigree reconstruction and molecular investigations in genes encoding type IV collagen chains, when DNA samples were available; and (e) follow-up data.

RESULTS

Renal biopsy analysis revealed no light microscopy changes in 27 patients and minimal abnormalities in the remainder. Global glomerular sclerosis was found in seven cases and superimposed mesangial immunoglobulin-A deposits in four. Normal staining of GBM for alpha(IV) chains was observed in all but one patient, where alpha5(IV) was absent and molecular investigation revealed a COL4A5 mutation. Five out of 25 cases had a mutation in the COL4A3/COL4A4 genes. Eight out of 38 patients followed up for 12-240 months (21%) showed signs of disease progression or hypertension.

CONCLUSIONS

This study confirms that a considerable proportion of patients with TBMD have a type IV collagen disorder and that this lesion is not always benign. Thus, families should be investigated carefully whenever possible and patients and affected relatives should be examined periodically for signs of disease progression.

The fate of glomerular mesangial IgA deposition in the donated kidney after allograft transplantation

OBJECTIVE

To investigate the fate of the mesangial IgA deposits in the donor kidney after allograft transplantation.

METHODOLOGY

Routine pre-transplant cadaveric donor kidney biopsy and repeated renal biopsies were performed at months 1, 3, and 6 after renal transplantation. The patients, 342 in number, were divided into IgA positive deposition kidney group (group A, n = 83) and non-IgA deposition kidney group (group B, n = 259). There were no significant differences between the two groups' sex, age, time of hemodialysis, warm ischemia time, cold ischemia time, complement-dependent cytotoxicity, level of panel-reactive assay, and the distribution of original disease.

RESULTS

Recipients in group A received donor kidney with glomerular mesangial proliferation and marked diffuse granular IgA deposition. All of them showed edema, nephrotic range protienuria, microhematuria, hypoalbuminemia, hypertension, and delayed graft function. Borderline change was higher in group A than in group B, 37.3 and 16.2% (p < 0.001), respectively. Acute allograft rejection was higher in group A than in group B, 31.3 and 19.3% (p < 0.001), respectively. The glomerular mesangial IgA deposits gradually disappeared from the mesangial regions in grafts of acute rejection. Graft survival in both groups was not significant, being 93.8 and 95.6% in 1 yr, and 86.7 and 88.3% in 3 yr.

CONCLUSION

Clinical features of the recipients which received from donor kidney with glomerular mesangial proliferation and marked diffuse granular IgA deposition: edema, proteinuria, microhematuria, hypoalbuminemia, hypertension, and delayed graft function. The presence of IgA deposits on donated kidney, by a possible increase of the immunogenicity of these kidneys, might be a cause of increased rejection. There were no significant differences between the two groups on long-term allograft survival.