Metástasis cutáneas como primera manifestación de neuroblastoma primario de glándula suprarrenal en un paciente pediátrico / Cutaneous metastasis as the first manifestation of primary adrenal gland neuroblastoma in a pediatric patient

Resumen Introducción: El neuroblastoma es el tumor maligno más frecuente en el primer año de vida y el tumor sólido extracraneal más frecuente en la infancia. Solo el 1% de los casos debuta con metástasis cutáneas, caracterizadas por nódulos azulados subcutáneos. Se presenta el caso de un lactante con un neuroblastoma suprarrenal izquierdo en el que las metástasis cutáneas constituían el síntoma principal. Caso clínico: Lactante de sexo femenino, de 2 meses de edad, sin antecedentes de importancia para el padecimiento actual. Acudió por presentar dermatosis diseminada en la región cervical y occipital, el abdomen, el muslo derecho y el pie izquierdo. La dermatosis se caracteriza por nódulos subcutáneos, sólidos, bien delimitados, < 1 cm, de color azulado, que iniciaron su aparición a los 7 días de vida en el hipocondrio derecho, con crecimiento progresivo, asintomáticos. Se realizó biopsia de un nódulo y se reportó la presencia de células pequeñas con núcleo denso hipercromático, escaso citoplasma y dispuestas en nidos. La inmunohistoquímica fue positiva para cromogranina y enolasa neuronal específica. Los hallazgos fueron compatibles con metástasis cutánea de neuroblastoma. Se solicitó valoración y abordaje por oncología pediátrica, que reportó un estadio 4 de la enfermedad y se inició el tratamiento correspondiente. Conclusiones: Los pediatras y los dermatólogos pediatras son los primeros en atender a niños con alguna lesión cutánea. Se deben tener en cuenta las metástasis cutáneas, que pueden aparecer antes o simultáneamente al diagnóstico de un tumor primario. Por lo tanto, se debe realizar un correcto abordaje con el fin de mejorar el pronóstico y la calidad de vida del paciente.

Abstract Background: Neuroblastoma is the most common malignant tumor in the first year of life and the most common extracranial solid tumor in childhood. Only 1% of cases present with cutaneous metastases characterized by subcutaneous bluish nodules. We report the case of an infant with a left adrenal neuroblastoma in whom skin metastases were the main symptom. Case report: Two-month-old female infant with no relevant history for the current condition. The infant presented disseminated dermatosis affecting the head in the cervical and occipital region, abdomen, right thigh and left foot. Dermatosis was characterized by subcutaneous nodules, solid, well limited, < 1 cm, bluish color that appeared at 7 days of life in the right upper quadrant, with progressive growth, asymptomatic. A biopsy of a nodule was performed, which reported the presence of small cells with a dense hyperchromatic nucleus, scarce cytoplasm, arranged in nests. Immunohistochemistry was positive for chromogranin and specific neuronal enolase. Findings were consistent with cutaneous neuroblastoma metastasis. An assessment and approach by pediatric oncology were requested, reporting disease stage 4 and initiating the corresponding treatment. Conclusions: Pediatricians and pediatric dermatologists are the first to attend to children with a skin lesion. We must consider that skin metastases may appear prior to or simultaneously with the diagnosis of a primary tumor. Therefore, we should carry out a correct approach in order to improve the prognosis and the quality of life of the patient.

[Cutaneous metastasis as the first manifestation of primary adrenal gland neuroblastoma in a pediatric patient.] / Metástasis cutáneas como primera manifestación de neuroblastoma primario de glándula suprarrenal en un paciente pediátrico

Introducción: El neuroblastoma es el tumor maligno más frecuente en el primer año de vida y el tumor sólido extracraneal más frecuente en la infancia. Solo el 1% de los casos debuta con metástasis cutáneas, caracterizadas por nódulos azulados subcutáneos. Se presenta el caso de un lactante con un neuroblastoma suprarrenal izquierdo en el que las metástasis cutáneas constituían el síntoma principal. Caso clínico: Lactante de sexo femenino, de 2 meses de edad, sin antecedentes de importancia para el padecimiento actual. Acudió por presentar dermatosis diseminada en la región cervical y occipital, el abdomen, el muslo derecho y el pie izquierdo. La dermatosis se caracteriza por nódulos subcutáneos, sólidos, bien delimitados, < 1 cm, de color azulado, que iniciaron su aparición a los 7 días de vida en el hipocondrio derecho, con crecimiento progresivo, asintomáticos. Se realizó biopsia de un nódulo y se reportó la presencia de células pequeñas con núcleo denso hipercromático, escaso citoplasma y dispuestas en nidos. La inmunohistoquímica fue positiva para cromogranina y enolasa neuronal específica. Los hallazgos fueron compatibles con metástasis cutánea de neuroblastoma. Se solicitó valoración y abordaje por oncología pediátrica, que reportó un estadio 4 de la enfermedad y se inició el tratamiento correspondiente. Conclusiones: Los pediatras y los dermatólogos pediatras son los primeros en atender a niños con alguna lesión cutánea. Se deben tener en cuenta las metástasis cutáneas, que pueden aparecer antes o simultáneamente al diagnóstico de un tumor primario. Por lo tanto, se debe realizar un correcto abordaje con el fin de mejorar el pronóstico y la calidad de vida del paciente.

Renal globotriaosylceramide deposits for Fabry disease linked to uncertain pathogenicity gene variant c.352C>T/p.Arg118Cys: A family study.

BACKGROUND: Fabry disease (FD) has an extensive phenotypic expression associated with GLA gene variants. The GLA gene variant c.352C>T/p.Arg118Cys was considered with uncertain pathogenicity because of the finding of high residual alpha-galactosidase A (α-Gal A) enzyme activity, the absence of Mendelian segregation with an FD phenotype with many individuals remaining asymptomatic at old ages and the lack of globotriaosylceramide (Gb3) deposits in tissues. Gb3 deposits are found in kidneys before the progression to overt microalbuminuria and decreased glomerular filtration. METHODS: We describe a family with c.352C>T/p.Arg118Cys variant and pathognomonic signs of FD renal damage in masculine children. RESULTS: The proband died of end-stage renal failure and we analyzed GLA gene in his offspring and found the variant in all daughters and five of seven grandchildren. In patients who we measure plasma and urinary Gb3, α-Gal A enzyme activity, and plasma globotriaosylsphingosine (Lyso-Gb3), these were normal or almost normal. A kidney biopsy was performed in two boys and one girl with normal renal function and characteristic signs of FD as enlarged and vacuolated epithelial cells, myelin figures, myelin-like figures, lamellated structures in podocytes and endothelial cells, were found in boys. These boys received agalsidase beta 1 mg/kg IV infusion every other week to prevent further renal damage. CONCLUSION: This is the first report that shows a link between FD renal Gb3 deposits and c.352C>T/p.Arg118Cys variant, supporting pathogenicity of a variant considered until now with uncertain pathogenicity.

Randomized Controlled Trial of Mineralocorticoid Receptor Blockade in Children with Chronic Kidney Allograft Nephropathy.

BACKGROUND AND OBJECTIVES: We showed that mineralocorticoid receptor blockade (MRB) prevented acute and chronic cyclosporine nephropathy (CsA-Nx) in the rat. The aim of this translational study was to investigate the effect of long-term eplerenone administration on renal allograft function in children with biopsy-proven chronic allograft nephropathy (CAN). DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Renal transplant children <18 years, biopsy-proven CAN, and a GFR>40 ml/min per 1.73 m2 were included. Patients with BK virus active nephritis, recurrence of renal disease, GFR decline in previous 3 months, or treated with calcium antagonists or antifungal drugs were excluded. They were randomized to receive placebo (n=10) or eplerenone 25 mg/d for 24 months (n=13). Visits were scheduled at baseline, 6, 12, and 24 months. At each period, a complete clinical examination was performed and blood and urine samples were taken. Urine creatinine, 8-hydroxylated-guanosine, heat shock protein 72 (HSP72), and kidney injury molecule (KIM-1) levels were also assessed. In kidney biopsy samples, the tubulo-interstitial area affected by fibrosis (TIF) and glomerulosclerosis were measured at baseline and after 24 months. RESULTS: The baseline eGFR was 80±6 in the placebo and 86±6 ml/min per 1.73 m2 in the eplerenone group; at 24 months it was 66±8 and 81±7 ml/min per 1.73 m2, respectively (P=0.33; 95% confidence intervals, -18 to 33 at baseline, and -11 to 40 after 24 months). The albumin-to-creatinine ratio was 110±74 in the placebo, and 265±140 mg/g in the eplerenone group; and after 24 months it was 276±140 and 228±88 mg/g, respectively (P=0.15; 95% confidence intervals, -283 to 593, and -485 to 391, respectively). In addition, the placebo exhibited a greater TIF, glomerulosclerosis, and urinary HSP72 compared with the eplerenone group. CONCLUSIONS: Although this study was underpowered to provide definitive evidence that long-term eplerenone administration attenuates the progression of CAN in pediatric transplant patients, it encourages testing the potential benefit of MRB in this pediatric population.

Urinary MCP-1/creatinine in Henoch-Schönlein purpura and its relationship with nephritis.

BACKGROUND: Monocyte chemotactic protein-1 (MCP-1) plays a direct role in the infiltration of macrophages and monocytes during the early stages of Henoch-Schönlein purpura (HSP) nephritis. The aim of this study was to compare the urinary MCP-1/creatinine levels in children with and without HSP nephritis and determine if they are associated with the severity of renal lesions. METHODS: We included 77 patients with HSP and 25 healthy control children. Levels of serum creatinine, urinalysis, and 12-h proteinuria assessments were performed. Urinary MCP-1 levels were determined by ELISA. RESULTS: Fifty-seven patients had nephritis (74 %). Urinary MCP-1/creatinine levels were significantly higher in patients with HSP nephritis (median, 653 pg/mg) compared to those with HSP without nephritis (median, 269 pg/mg) or healthy children (191 pg/mg). In addition, higher MCP-1/creatinine levels were observed in HSP patients who had renal biopsy (median, 1,412 pg/mg) in comparison to HSP patients without renal biopsy (median, 302 pg/mg). The urinary MCP-1 cut-off value of 530 pg/mg could be used to distinguish patients who undergo renal biopsy with a sensitivity of 81 % and specificity of 77 %. CONCLUSIONS: Urinary MCP-1/creatinine levels are elevated in the early stages of severe HSP nephritis and can be used as a biomarker for HSP nephritis.

[Hirschsprung's disease: the immunohistochemistry as ancillary method for the diagnosis.] / Enfermedad de Hirschsprung. La inmunohistoquímica como apoyo para el diagnóstico.

Background: the confirmatory diagnosis of Hirschsprung's disease is made by histopathological study. However, this procedure is limited with only hematoxylin and eosin staining, especially in biopsies of premature babies or when non-expert pathologists make the evaluation. The immunohistochemistry from ganglia cell calretinin has been used to reduce the risk of misdiagnosis. Our objective was to show the benefits of this antibody in diagnosis of Hirschsprung's disease in biopsy specimens. Methods: we evaluated patients with histopathological diagnosis of Hirschsprung's disease made by hematoxylin and eosin staining. We determined if there was enough paraffin block for immunohistochemistry with two markers: calretinin and neurofilaments. Three controls of autopsy of children under 3 years of age with other diagnosis were included. Results: of a total of 48 cases with histopathological diagnosis of Hirschsprung's disease only 13 had adequate tissue for immunohistochemistry. The immunohistochemistry confirmed the diagnosis in nine cases. In the other four cases there were initial misdiagnosis due to evidence of calretinin (ganglion cells) and, thus, Hirschsprung's disease was discarded. Conclusions: the use of immunohistochemistry allows confirming the diagnosis of Hirschsprung's disease and reduce the risk of a false-positive result with only hematoxylin and eosin staining.

Introducción: el diagnóstico de certeza de la enfermedad de Hirschsprung es histopatológico, aunque puede ser erróneo si solo se utiliza hematoxilina y eosina, sobre todo en muestras de niños prematuros o evaluadas por patólogos inexpertos. Se ha recomendado la inmunohistoquímica para identificar las células ganglionares, lo que descarta la enfermedad. Nuestro objetivo es mostrar las ventajas de esta técnica. Métodos: se evaluaron los casos de enfermedad de Hirschsprung con diagnóstico histopatológico mediante tinción con hematoxilina y eosina. Se realizó inmunohistoquímica para dos marcadores: la calretinina y los neurofilamentos. Se incluyeron tres muestras de tejido de autopsias de niños menores de tres años con colon sin alteraciones aparentes. Resultados: de 48 casos con diagnóstico histopatológico de enfermedad de Hirschsprung, solo 13 tuvieron bloque de parafina con tejido suficiente. La inmunohistoquímica confirmó el diagnóstico en nueve. En los otros cuatro hubo error diagnóstico inicial, dada la evidencia de calretinina (células ganglionares) y con ello se descartó la enfermedad de Hirschsprung. Conclusiones: el uso de la inmunohistoquímica para identificar calretinina permitió descartar el diagnóstico de enfermedad de Hirschsprung y evitar la emisión de diagnósticos falsos positivos.

Toll-like receptors and cytokines are upregulated during Helicobacter pylori infection in children.

BACKGROUND AND AIM: Helicobacter pylori infection is mainly acquired during childhood, and establishes a chronic infection that may lead to peptic ulcer or gastric cancer during adulthood. Toll-like receptors (TLRs) are expressed by distinct cell types throughout the gastrointestinal tract, and play an important role in regulation of the innate immune response. Few works have addressed TLRs expression in gastric epithelia of adults, and scarce studies have done it in children. The aim of this work was to analyze the expression of TLR2, TLR4, TLR5, TLR9, and IL-8, IL-10 and TNF-α in the gastric mucosa of children with and without H. pylori infection. METHODS: Gastric biopsies were collected by endoscopy from 50 children with recurrent abdominal pain, 25 with H. pylori infection and 25 without infection. In the gastric biopsies the expression of TLRs and cytokines was studied by immunohistochemistry, and the degree of mucosal inflammation was determined using the Sydney system. RESULTS: We found that H. pylori infection was associated with a significant increased expression of TLRs 2, 4, 5 and 9, although expression varied between surface epithelia and glands. Epithelial cells expressing IL-8, IL-10 and TNF-α were increased in gastric mucosa of children with H. pylori infection. CONCLUSION: This study shows the gastric epithelia of children respond to H. pylori infection by increasing the expression of TLR2, TLR4, TLR5, TLR9 and the cytokines IL-8, IL-10 and TNF-α.

Non-invasive markers of liver fibrosis in chronic liver disease in a group of Mexican children. A multicenter study.

INTRODUCTION: Identifying liver fibrosis is important to evaluate the severity of liver damage and to establish a prognosis. Utility of non-invasive markers of liver fibrosis has been proved in adults but there are few reports in children. The aim of this study was to evaluate Fibrotest® score and APRI suitability to identify children with liver fibrosis. MATERIAL AND METHODS: 68 children with chronic liver disease requiring liver biopsy were prospectively included from three 3rd-level pediatric hospitals. The same pathologist evaluated all liver biopsies; fibrosis degree was determined by METAVIR score. Serum samples were obtained to determine Fibrotest® and APRI. AUROC were used to determine cut-off and differentiate between advanced fibrosis (METAVIR F3, F4) and no fibrosis (F0). RESULTS: 68 biopsies were evaluated; METAVIR > F3 was identified in 26 (38%). Non invasive liver fibrosis markers to differentiate between advanced and no fibrosis were: Fibrotest® AUROC = 0.90 (95% CI 0.77-1.00) (cut-off value 0.35) sensitivity 88.00% (95% CI 68-96) and specificity 80% (95% CI 29-98); and for APRI AUROC = 0.97 (95% CI 0.92-1.00) (cut-off value 0.82), sensitivity 88% (95% CI 68-96) and specificity = 100% (95% CI 46-100). CONCLUSION: These results suggest the utility of Fibrotest® and APRI to identify advanced fibrosis; they can be recommended to select patients for liver biopsy and during patient follow-up.

Anticuerpos anti-HLA y rechazo agudo del injerto renal en los niños / Anti-HLA antibodies and acute renal graft rejection in children

Introducción. A pesar de que las nuevas terapias inmunosupresoras han mejorado notablemente la evolución clínica de los trasplantes renales, los rechazos agudo y crónico siguen limitando la sobrevida a largo plazo del injerto. En base a lo anterior, el objetivo de este estudio fue determinar la presencia de anticuerpos séricos contra antígenos de histocompatibilidad (HLA) clase I y clase II en niños con rechazo agudo del injerto renal. Métodos. Se realizó un estudio clínico prospectivo en pacientes con trasplante renal que presentaron rechazo agudo del injerto. Se les tomó muestra de suero al momento de la biopsia renal, misma que fue utilizada para la detección de anticuerpos contra antígenos HLA de clase I y II por ensayo basado en equipo fuoroanalizador (Luminex) y microperlas cubiertas con antígenos clase I y clase II de One Lambda. Resultados. De 21 pacientes estudiados, 17 pacientes (81%), fueron diagnosticados con rechazo celular y cuatro (19%) con rechazo agudo mediado por anticuerpos. El tiempo post-trasplante promedio de presentación del rechazo humoral agudo fue de 18.7 meses y para el rechazo celular de 36.7 meses. Once pacientes (52.3%) presentaron anticuerpos específicos contra el donador. Los anticuerpos contra antígenos HLA clase I donador específicos se encontraron en seis pacientes, siendo más frecuente el rechazo agudo mediado por anticuerpos (humoral), donde todos los pacientes tuvieron anti HLA clase I con Chi cuadrada (P =0.004). En cuanto a los anticuerpos inespecíficos, el 95.2% de los pacientes desarrollaron este tipo de anticuerpos. Conclusiones. El 95% de los niños con rechazo del injerto renal presentan anticuerpos anti HLA, específicos y/o no específicos contra el donador. Los anticuerpos anti HLA donador específicos clase I se presentan con mayor frecuencia en el rechazo humoral.

Background. Although new immunosuppressive therapies have signifcantly improved the clinical progression of kidney transplants, acute and chronic rejection continue to limit long-term graft survival. Despite this, the aim of the study was to determine the presence of human leukocyte antigen (HLA) antibodies class I and class II in children with acute renal graft rejection. Methods. Patients with graft rejection were included in the study. A serum sample for anti-HLA antibody measurement class I and II by Luminex was taken at the time of renal biopsy. Results. Seventeen patients (81%) had cellular rejection and four (19%) antibody-mediated rejection. Mean post-transplant time of rejection was 18.7 months and 36.7 months for humoral rejection and cellular rejection, respectively. Eleven patients (52.3%) had donor specific (DS) antibodies. Anti-HLA class I DS was found in six patients including the four patients with humoral rejection (Fisher exact test p =0.004); 95.2% had non-DS antibodies. Conclusions. Of the children with acute renal graft rejection, 95% have anti HLA antibodies (DS and/or non-DS). Anti-HLA DS class I are more frequent in humoral rejection.

[Focal segmental glomerulosclerosis related to BK virus in a child with nephrotic syndrome. A case report]. / Glomerulopatía colapsante asociada a virus BK en un niño con síndrome nefrótico idiopático. Informe de un caso.

BACKGROUND: focal segmental glomerulosclerosis (FSGS) is observed in about 10 % of children with idiopathic nephrotic syndrome; this disorder is usually resistant to corticoid therapy. In the last few years, five histological types of FSGS have been recognized; the collapsing nephropathy type is characterized by a rapid evolution to chronic renal failure. CLINICAL CASE: a four-year-old boy presented with an irrelevant past history; eight months before admission he developed idiopathic nephrotic syndrome. He was treated with steroids without improvement, and a renal biopsy was performed in which minimal glomerular changes were found. Despite combined immunosuppressive treatment, he developed renal failure, septic shock and death. Collapsing nephropathy was demonstrated by immunohistochemistry, light and electron microscopy; renal new human papovirus (BK) infection was also found in the postmortem study. CONCLUSIONS: collapsing nephropathy is an aggressive disorder resistant to immunosuppressive treatment, as occurred in our patient. Although some viral diseases have been associated with collapsing nephropathy, to our knowledge, BK infection has not been previously described in those patients.

pRB detection as a common event in human retinoblastomas: an immunohistochemical study.

Approximately 30% of the cases of retinoblastoma (RB), the childhood eye cancer, are inherited and are manifested by unilateral or bilateral tumor. In sporadic tumors, accounting for 70% of cases, only one eye is affected. RB has three histological features: undifferentiated anaplastic cells, retinoblast pattern, and differentiated pattern characterized by Flexner Wintersteiner rosettes (FWR). Currently, results concerning phosphoprotein RB (pRB) expression in RB tumors are contradictory. In this study we detected pRB immunohistochemically in 10 tumors from bilateral or unilateral RBs, which did not show gross chromosomal alterations in cytogenetic studies. Interestingly, pRB was undetectable in only one tumor where we found distinct histological features. Our results suggest that pRB immunopositivity may be common in these tumors. However, it does not rule out the possibility that pRB is functionally inactive in some cases. This may be due to the protein being present in phosphorylated form or being altered by point mutations not affecting its expression. Another possibility is that mechanisms other than RB1 gene changes may lead to retinoblastoma because not all cases of retinoblastoma show gene alterations. Together these findings may be useful in understanding the molecular mechanisms associated with this type of pediatric tumor.

Cutoff value of lipid-laden alveolar macrophages for diagnosing aspiration in infants and children.

Chronic passage of gastric and/or alimentary material into the airways is a frequent and difficult-to-diagnose condition. Because alveolar macrophages phagocytose aspirated material, it has been suggested that their identification is a useful diagnostic method. To know the usefulness of the lipid-laden alveolar macrophages (LLAM) index as a diagnostic tool for aspiration, children from 1 month to 16 years of age were included in three groups: G-I, children with pulmonary pathology and suspicion of aspiration by clinic or image evaluation; G-II, with pulmonary pathology without suspicion of aspiration; and G-III, without respiratory symptoms nor suspicion of aspiration. Bronchoalveolar lavage was obtained through bronchoscopy in G-I and G-II, and through endotracheal tube in G-III, and the LLAM index (0-400) was determined. A total of 112 patients (41, 30, and 41 in G-I to III, respectively) were studied. LLAM index (mean +/- SEM) was highest in G-I (233.2 +/- 5.5), as compared with G-II (187.8 +/- 11.6, P < 0.05), and G-III (108.5 +/- 13.5, P < 0.001). However, notable overlap of LLAM values was observed between G-I and G-II, and between G-II and G-III. When patients from G-I and G-III were jointly analyzed, the area under the ROC curve for diagnosing aspiration was 0.92, with a best cutoff value of >165 (98.6% sensitivity, 78.0% specificity, 87.8% overall accuracy). LLAM index, with a cutoff value of >165 is a useful diagnostic test for aspiration when there is suspicion of this condition. However, due to its low specificity, it does not discriminate other causes of chronic lung disease.

Púrpura de Henoch-Schönlein: Reporte de 105 pacientes pediátricos / Henoch-Schönlein purpura in children: Report of 105 patients

Introducción. La púrpura de Henoch-Schönlein (PHS) es la vasculitis más frecuente en niños. Objetivo: conocer la presentación clínica y evolución de los pacientes con PHS que se han tratado en el hospital en los últimos 5 años. Material y métodos. Estudio retrospectivo en pacientes que acudieron al Hospital Infantil de México Federico Gómez, del 1 de enero de 2000 al 31 de diciembre de 2005, con diagnóstico de PHS. Resultados. Se encontraron 105 pacientes con una mediana de edad de 6 años. El tiempo promedio de seguimiento fue de 15 meses. Todos presentaron lesiones dérmicas, 49.5% dolor abdominal y 41% artritis; 45 (42.9%) pacientes manifestaron nefropatía, con un promedio de aparición de 4.5 meses después de las lesiones dérmicas. Sólo en 37.7% de los casos con nefropatía desaparecieron las alteraciones urinarias. Se realizó biopsia renal en 14 pacientes. La lesión histopatológica más frecuente fue el grado IIIA. La edad de presentación tuvo relación estadísticamente significativa con la presencia de nefritis, los mayores de 10 años tuvieron mayor incidencia de nefritis y los menores de 5 años menor incidencia (Chi cuadrada, P < 0.05). La incidencia global de insuficiencia renal crónica fue de 0.95%. Conclusión. La edad de presentación es un factor pronóstico para la evolución de la enfermedad. Si bien la púrpura es una vasculitis, la principal complicación a largo plazo es renal, por lo que el seguimiento de los pacientes debe ser supervisado por un nefrólogo pediatra.

Introduction. Henoch-Schönlein purpura (HSP) is the most frequent vasculitis in children. Objective: To describe the clinical presentation and clinical outcome in children with HSP treated in our hospital in the last 5 years. Material and methods. A retrospective study was performed in HSP patients diagnosed between January 1st 2001 and December 31st 2005. Results. HSP was diagnosed in 105 patients, median age 6 years old. All had the skin manifestations, 49.5% abdominal pain and 41% arthritis; 45 patients developed HSP nephritis (42.9%), mean presentation time was 4.5 months after HSP diagnosis. Renal biopsy was performed in 14 patients, and the most common histopathological finding was HSP nephritis grade III A. Age of onset older than 10 years was statistically significant for nephritis development (Chi Square < 0.05). Chronic renal insufficiency incidence was 0.95%. Conclusions. The main complication of HSP is nephritis. Follow-up should include evaluation by a pediatric nephrologist. Age of onset older than 10 years is an important risk factor for HSP nephritis.