Idiopathic nephrotic syndrome in children: review of 282 Croatian cases.

Recent data suggests increased incidence of focal segmental glomerulosclerosis (FSGS) among children with idiopathic nephrotic syndrome (INS). To determine the causes and possible longitudinal changes in the etiology of INS, 282 Croatian children diagnosed with INS between 1990 and 2009 were evaluated. In total, 122 children were assessed as having minimal change nephrotic syndrome (MCNS) based on their initial presentation, laboratory findings and clinical course. Kidney biopsy was performed in the remaining 160 children. MCNS was present in 18.1% of all biopsies performed. Total incidence of MCNS (assessed + biopsy proven) was only 53.5%. In contrast, FSGS was found in 40.6% of all biopsies and accounted for 23.1% of all cases. Mesangial proliferative glomerulonephritis (MesPGN) was the third most common diagnosis, present in 26.9% of the biopsies, and accounted for 15.2% of all cases. There were no significant longitudinal differences in the incidence of different causes of INS. The overall response to steroids at presentation was 71.6%. A higher proportion of initial steroid responders among children with FSGS (43.1%) and MesPGN (67.4%) than previously reported was noted. A longitudinal tendency of increasing steroid resistance in FSGS and MesPGN groups was observed.

[Clinical and histopathological characteristics of biopsy-proven renal diseases in Croatia]. / Klinicke i patohistoloske karakteristike biopsijom dokazanih bubreznih bolesti djece u Hrvatskoj.

There is little data on the spectrum of renal diseases in children in Croatia. The Croatian Society for Pediatric Nephrology has established the Registry of Biopsy-Proven Renal Diseases in an attempt to address this issue nationwide. Here we report preliminary results of a retrospective analysis of clinical and histopathological data of 565 children aged < or =17 years presenting to 9 hospitals in Croatia from 1991 to 2004, in whom kidney biopsy was performed. The most common indication for renal biopsy was nephrotic syndrome (39.1%), followed by asymptomatic proteinuria/hematuria (22.0%) and acute nephritic syndrome (17.0%). All biopsies were analysed by light-, immunofluorescent and electron microscopy. The majority of children, 552 out of 565 (92.4%), had glomerulonephritis (GN). Tubulointerstitial nephritis was found in 16 (2.8%), congenital renal parenchyma anomalies in 14 (2.5%) and vascular disease in 11 (1.9%) cases. One (0.2%) child had sarcoidosis with nephrocalcinosis. The sample was non-diagnostic in 1 (0.2%) case. Among children with GN, primary GN accounted for 70.9%, secondary GN for 16.1% and hereditary GN for 13.0% cases. The most frequent primary GN forms were focal segmental glomerulosclerosis (FSGS) (24.6%), mesangial proliferative glomerulonephritis (MEPGN) (19.2%) and IgA nephropathy (18.1%). Acute GN in resolution was found in 11.1% and minimal changes GN in 6.8% of cases. Most children with secondary GN had nephritis of Henoch-Schönlein purpura (HSP) (54.7%) and nephritis of systemic lupus erythematosus (SLE) (40.5%), while among hereditary GN Alport syndrome was most common (80.9%). In the group of children with primary GN who presented with nephrotic syndrome, most common forms were FSGS (38.5%) and MEPGN (24.0%). Minimal changes GN accounted for only 10.9% of cases. IgA nephropathy, primary or related to HSP (20.0%), FSGS (16.1%), MEPGN (12.6%) and Alport syndrome (9.7%) were the most common biopsy-proven renal diseases in Croatian children. The analysis provided data on the frequency of histological renal lesions in children in Croatia. The higher frequency of FSGS and MEPGN among Croatian children in comparison with other countries deserves further evaluation.

Bioactive 1,4-dihydroisonicotinic acid derivatives prevent oxidative damage of liver cells.

1,4-Dihydroisonicotinic acid derivatives (1,4-DHINA) are compounds closely related to derivatives of 1,4-dihydropyridine, a well-known calcium channel antagonists. 1,4-DHINA we used were derived from a well-known antioxidant Diludin. Although some compounds have neuromodulatory or antimutagenic properties, their activity mechanisms are not well known. This study was performed to obtain data on antioxidant and bioprotective activities of: 2,6-dimethyl-3,5-diethoxycarbonyl-1,4-dihydroisonicotinic acid (Ia); sodium 2-(2,6-dimethyl-3,5-diethoxycarbonyl-1,4-dihydropyridine-4-carboxamido)glutamate (Ib) and sodium 2-(2,6-dimethyl-3,5-diethoxycarbonyl-1,4-dihydropyridine-4-carboxamido)ethane-sulphate (Ic). 1,4-DHINA's activities were studied in comparison to Trolox by: N,N-Diphenyl-N'-picrylhydrazyl (DPPH*), deoxyribose degradation, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical scavenging and antioxidative capacity assays; copper-induced lipid peroxidation of cultured rat liver cells (malondialdehyde determination by high performance liquid chromatography and 4-hydroxynonenal-protein conjugates by dot-blot); (3)H-thymidine incorporation and trypan blue assay for liver cells growth and viability. In all assays used Ia was the most potent antioxidant. Ia was also a potent antioxidant at non-toxic concentrations for liver cell cultures. It completely abolished, while Ic only slightly decreased copper-induced lipid peroxidation of liver cells. Thus, antioxidant capacities are important activity principle of Ia, which was even superior to Trolox in the cell cultures used, while activity principles of Ic and Ib remain yet to be determined.

Possible involvement of 4-hydroxynonenal in splenocyte regulated liver regeneration.

Liver regeneration is a complex, systemic process regulated by humoral and cellular mechanisms. Inflammatory response to the extensive tissue damage, as in partial hepatectomy, plays important role during regeneration. Hence, it is assumed that the spleen might play a role in systemic inflammatory response involved in liver regeneration. On the other hand, liver damage and consequential regeneration are often associated with oxidative stress and lipid peroxidation. One of the end products of lipid peroxidation, 4-hydroxynonenal (HNE), is nowadays considered not only as a "second toxic messenger of free radicals" but also as a growth-regulating factor. We therefore studied in vitro interactions of the HNE-treated murine liver cells and autologous spleen cells. The spleen cells supported recovery of liver cells from the HNE cytotoxicity although spleen cells themselves exerted cytotoxic effects against the proliferating liver cells that were not treated with HNE. Our results imply that the cytokines secreted by activated immunocompetent cells may be responsible for the observed recovery of the HNE-damage liver cells, suggesting that HNE might be an important factor regulating cellular and cytokine mediated mechanisms of liver regeneration control.

Patient with immunoproliferative disease and lung carcinoma: a case report.

There are a number of reports on collision occurrence of non-hematologic cancers and Non-Hodgkin's lymphoma (NHL) and multiple myeloma. In this report we present a case of patient with immunoproliferative disease, extramedullary plasmocytoma and NHL-lymphoplasmocytoid lymphoma (LPL) and squamous cell carcinoma of the lung. After diagnosis of extramedullary plasmocytoma cytostatic therapy was commenced and the patient was well. Five years after patient was clinically worse and diagnostic evaluation this time revealed lymphoplasmocytoid cells in bone marrow. Five months later malignant morphologically undifferentiated cells were found in bone marrow which were by immunocytochemistry established as CD38 positive. After the patient's death, disseminated NHL-LPL and squamous cell carcinoma of lung was confirmed. In the report, we compared clinical course and diagnostic findings of our patient with literature data. We have also discussed the possible relationship of multiple B-cell lymphoid tumors and squamous cell carcinoma concluding that multidiscplinary diagnostic tools are essential not only for carcinoma diagnosis and follow-up, but also for further understanding of carcinogenesis.

[Renal biopsy in children with isolated microhematuria]. / Biopsija bubrega u djece s izoliranom mikrohematurijom.

UNLABELLED: Isolated microscopic hematuria (IMH) in children always raises the question whether, besides other examinations, there is a need of performing a renal biopsy. Many authors consider IMH to be a minor abnormality where pathologic glomerular changes are not likely to be found, however, general agreement has not yet been achieved. The aim of the study was to evaluate the contribution of renal biopsy to the diagnosis of the disease in IMH. PATIENTS AND METHODS: Renal biopsy was performed in 54 children with IMH (22 boys and 32 girls, mean age 8.2 and 8.5 years, respectively) in whom urologic abnormalities, hypercalciuria, systemic diseases, coagulopathy or overt family history of renal disease were excluded. The mean duration of IMH prior to biopsy was 2.8 years. Biopsy specimens were examined by light (LM), immunofluorescent (IF) and electron microscopy (EM). RESULTS: Glomerular abnormalities were found in 43 (79.6%) patients. On LM 18 patients had normal glomeruli (NG), 22 mesangial proliferative glomerulonephritis (MEPGN), 9 focal glomerulosclerosis (FGS), 3 focal glomerulonephritis (FGN) and 2 membranoproliferative glomerulonephritis (MPGN). IF revealed 2 cases of NG, 5 cases of MEPGN, and all 3 cases of FGN as IgA nephropathy. EM detected GBM changes consistent with Alport syndrome in 21 patients, 7 of them with NG, 9 with MEPGN and 5 with FGS on LM. Diffuse thinning of GBM was found in 10 children, 7 with NG and 3 with MEPGN on LM. In 5 cases subepithelial hump-like deposits, which were considered to be the sign of acute postinfectious glomerulonephritis in resolution, were found. One of 2 cases of MPGN showed to be type II (DDD). On follow-up, 6 of 21 children with changes consistent with Alport syndrome developed clinical signs of the syndrome. Further surveillance is needed to confirm the significance of EM findings in others. CONCLUSION: The authors concluded that in children with IMH renal biopsy is justified and should always be analyzed by light, immunofluorescent and electron microscopy.

Influence of 4-hydroxynonenal and spleen cells on primary hepatocyte culture and a novel liver-derived cell line resembling hepatocyte stem cells.

Liver is a unique mammalian organ with a great capacity of regeneration related to its function. After surgical resection or injury, hepatic cells, especially hepatocytes, can proliferate rapidly to repair the damage and to regenerate the structure without affecting the function of the liver. Loss of catalase activity during regeneration indicates that oxidative stress is present in the liver not only in pathological conditions but also as a 'physiological' factor during regeneration. As we have shown in our previous work, liver stem cell-like cells treated with 4-hydroxynonenal (HNE), a cytotoxic and growth regulating lipid peroxidation product, recover in the presence of spleen cells. In the current study we characterized this novel cell line as liver-derived progenitor/oval-like cells, (LDP/OCs), i.e. functional liver stem-like cells. We showed that LDP/OC were OV6 positive, with abundant glycogen content in the cytoplasm and expressed alpha-fetoprotein, albumin, biliverdin reductase and gamma-glutamyl transferase. Also, we compared their growth in vitro with the growth of cultured primary hepatocytes stressed with HNE and co-cultured with autologous spleen cells. The influence of spleen cells on HNE-treated primary hepatocytes and on LDP/OCs showed that spleen cells support in a similar manner the recovery of both types of liver cells indicating their important role in regeneration. Hence, LDP/OC cells may provide a valuable tool to study cell interactions and the role on HNE in liver regeneration.

Epidemiology of renal disease in children in the region of southern Croatia: a 10-year review of regional renal biopsy databases.

BACKGROUND: Epidemiological data on some renal diseases in children are available from world national registries of renal biopsies. However, there is no publislhed study of biopsy-proven childhood glomerulonephritis in Croatia. This report is the first review of pathohistological data covering a pediatric population over a 10-year period in the Croatian region of Dalmatia. MATERIAL/METHODS: A retrospective study was done on all renal biopsies from 65 children under 18 years of age received by the Clinical Hospital Split between 1995 and 2005. The histopathological findings were reviewed to determine the pattern of biopsy-proven glomerulonephritis. Indications for renal biopsy and clinico-pathological correlations were studied. Data on serum creatinine concentration, 24-h proteinuria, hematuria, clinical diagnosis, pathohistological diagnosis, and post-biopsy complications were collected. RESULTS: The main indications for biopsy were nephrotic syndrome (41.5%), hematuria with proteinuria (23.1%), and isolated hematuria (12.3%). The most frequent renal diseases in decreasing order were mesangioproliferative glomerulonephritis (27.7%), IgA nephropathy (13.8%), and Henoch-Schönlein nephritis (10.8%). Tubulointerstitial nephritis, focal segmental glomerulosclerosis, and endoproliferative glomerulonephritis each accounted for 6.2%. Alport syndrome, fibrillary glomerulonephritis, and minimal change diseases were each found in 4.6% of cases. Other forms of glomerulonephritis were rarely found. CONCLUSIONS: The present data represent the basis for a future Croatian Registry of Renal Biopsies and are an important contribution to the epidemiology of renal diseases in south-eastern Europe. Three cases of fibrillary glomerulonephritis in children with steroid-dependent nephrotic syndrome, not reported in other countries' registries, were also found. The importance of ultrastructural analysis of biopsy specimens is emphasized.

Thrombotic microangiopathy associated with alpha-interferon therapy for chronic myeloid leukaemia.

The association of interferon (IFN) therapy with haemolytic uraemic syndrome in patients with chronic myeloid leukaemia (CML) has been reported infrequently. The pathogenesis of the renal lesion in such cases remains unclear. We report the case of a patient with chronic myeloid leukaemia who developed nephrotic syndrome and renal failure while being treated with hydroxyurea and IFN-alpha. Renal biopsy showed features of chronic thrombotic microangiopathy. The discontinuation of IFN-alpha, and a prompt institution of plasmapheresis and steroids resulted in improvement of the nephrotic syndrome and renal function. These findings suggest that long-term IFN-alpha therapy can induce thrombotic microangiopathy and haemolytic uraemic syndrome in patients with chronic myeloid leukaemia.

Acute interstitial nephritis due to mesalazine.

A case of mesalazine-induced acute interstitial nephritis (AIN) in a 41-year-old patient with ulcerative colitis (UC) is reported here. Clinical symptoms such as fever and arthralgia, and laboratory findings such as eosinophilia and renal failure suggested AIN, which was confirmed by biopsy. With withdrawal of mesalazine and intravenous methylprednisolone the patient's renal function was recovered. It is observed that early discontinuation of mesalazine is associated with amelioration of interstitial nephritis in most patients, so the recommendation is that patients receiving mesalazine should undergo routine monitoring of renal function. Delayed diagnosis may lead to permanent renal function impairment.

Drug-induced acute tubulointerstitial nephritis: a case with elevated urinary cadmium.

Acute tubulointerstitial nephritis (ATIN) has many different causes, but is most frequently caused by drugs. We report a 13-year-old vegetarian girl with drug-induced ATIN, confirmed by renal biopsy, and simultaneous occurrence of elevated urinary cadmium. Four weeks prior to admission she had been treated with antibiotics and acetaminophen for respiratory infection, and remaining febrile, was treated with different "home-made" herbal mixtures. She presented with acute non-oliguric renal failure, tubular dysfunction, and sterile pyuria, but without skin rash or edema. Laboratory data showed a raised erythrocyte sedimentation rate, normal white blood count with eosinophilia, and a serum creatinine of 245 micromol/l. Urinalysis was remarkable for glycosuria, tubular proteinuria, and elevated beta(2)-microglobulin and N-acetyl-beta-D-glucosaminidase excretion. Immunoserological tests characteristic of acute glomerulonephritis and systemic diseases were negative. She was treated with steroids and her renal function improved. Follow-up analyses disclosed normal urinary cadmium and enzyme excretion within 6 months. Heavy metal analysis of herbal preparations that she had taken confirmed the presence of cadmium, but within approved concentrations. In conclusion, elevated urinary cadmium in the case of drug-induced ATIN may be assumed to be an accidental finding. However, consumption of different herbs containing cadmium and cadmium-induced nephro-toxicity could be the reason for such serious renal damage.

S-adenosylhomocysteine hydrolase deficiency in a human: a genetic disorder of methionine metabolism.

We report studies of a Croatian boy, a proven case of human S-adenosylhomocysteine (AdoHcy) hydrolase deficiency. Psychomotor development was slow until his fifth month; thereafter, virtually absent until treatment was started. He had marked hypotonia with elevated serum creatine kinase and transaminases, prolonged prothrombin time and low albumin. Electron microscopy of muscle showed numerous abnormal myelin figures; liver biopsy showed mild hepatitis with sparse rough endoplasmic reticulum. Brain MRI at 12.7 months revealed white matter atrophy and abnormally slow myelination. Hypermethioninemia was present in the initial metabolic study at age 8 months, and persisted (up to 784 microM) without tyrosine elevation. Plasma total homocysteine was very slightly elevated for an infant to 14.5-15.9 microM. In plasma, S-adenosylmethionine was 30-fold and AdoHcy 150-fold elevated. Activity of AdoHcy hydrolase was approximately equal to 3% of control in liver and was 5-10% of the control values in red blood cells and cultured fibroblasts. We found no evidence of a soluble inhibitor of the enzyme in extracts of the patient's cultured fibroblasts. Additional pretreatment abnormalities in plasma included low concentrations of phosphatidylcholine and choline, with elevations of guanidinoacetate, betaine, dimethylglycine, and cystathionine. Leukocyte DNA was hypermethylated. Gene analysis revealed two mutations in exon 4: a maternally derived stop codon, and a paternally derived missense mutation. We discuss reasons for biochemical abnormalities and pathophysiological aspects of AdoHcy hydrolase deficiency.