[Focal congenital hyperinsulinism]

In congenital hyperinsulinemic hypoglycemia - the most common cause of persistent hypoglycemia in infancy - a focal lesion can be identified in 50% of the cases. With appropriate medical care based upon early diagnosis, these patients can be cured by the resection of the lesion rendering unnecessary long time medical care, and avoiding serious brain damage from recurrent hypoglycemic episodes. Genetic testing and 18F-fluoro-dihydroxyphenylalanine PET/CT imaging are essential for determining the best possible treatment. We report 2 cases of focal congenital hyperinsulinism - both male infants: 22 and 2 months of age - treated successfully with enucleation of the pancreas lesion (Semmelweis University, Budapest). Both patients had the pathognomonic mutation of the ABCC8 gene of the ATP-sensitive potassium channel. Radiologic imaging and histology confirmed the diagnosis, and after the operation, pharmacological treatment was terminated in both cases. During the follow-up period (5 and 1.5 years, respectively) they are euglycemic, with no morbidities attributed to the operation. We believe that these two operations for focal hyperinsulinism - diagnosed and localised by the above detailed genetic and specific radiological testing - were the first of their kind in Hungary. Based on the acquired experience, every necessary examination can be achieved in our country to improve patient care, reduce morbidity and medical costs. Orv Hetil. 2023; 164(47): 1877-1884.

Comprehensive genetic testing in children with a clinical diagnosis of ARPKD identifies phenocopies

BACKGROUND

Autosomal recessive polycystic kidney disease (ARPKD) is genetically one of the least heterogeneous ciliopathies, resulting primarily from mutations of PKHD1. Nevertheless, 13-20% of patients diagnosed with ARPKD are found not to carry PKHD1 mutations by sequencing. Here, we assess whether PKHD1 copy number variations or second locus mutations explain these cases.

METHODS

Thirty-six unrelated patients with the clinical diagnosis of ARPKD were screened for PKHD1 point mutations and copy number variations. Patients without biallelic mutations were re-evaluated and screened for second locus mutations targeted by the phenotype, followed, if negative, by clinical exome sequencing.

RESULTS

Twenty-eight patients (78%) carried PKHD1 point mutations, three of whom on only one allele. Two of the three patients harbored in trans either a duplication of exons 33-35 or a large deletion involving exons 1-55. All eight patients without PKHD1 mutations (22%) harbored mutations in other genes (PKD1 (n = 2), HNF1B (n = 3), NPHP1, TMEM67, PKD1/TSC2). Perinatal respiratory failure, a kidney length > +4SD and early-onset hypertension increase the likelihood of PKHD1-associated ARPKD. A patient compound heterozygous for a second and a last exon truncating PKHD1 mutation (p.Gly4013Alafs*25) presented with a moderate phenotype, indicating that fibrocystin is partially functional in the absence of its C-terminal 62 amino acids.

CONCLUSIONS

We found all ARPKD cases without PKHD1 point mutations to be phenocopies, and none to be explained by biallelic PKHD1 copy number variations. Screening for copy number variations is recommended in patients with a heterozygous point mutation.

A part-randomized study of intravenous oseltamivir in adolescents and adults

Seriously ill patients with influenza may be unable to take oral medication. The safety of intravenous oseltamivir was evaluated in adults and adolescents. This prospective, part-randomized study enrolled hospitalized patients aged ≥13 years with clinical or laboratory-confirmed influenza, who started study medication within 144 h of illness onset. Patients with normal renal function received oseltamivir 100 or 200 mg every 12 h for 5 days by slow intravenous infusion. Patients with renal impairment received lower doses, appropriate to the degree of impairment. Blood samples were taken for pharmacokinetics, and nasal swabs were taken to monitor viral shedding and resistance [reverse transcription polymerase chain reaction (RT-PCR) and culture]. Adverse events (AEs) were monitored for 30 days from treatment initiation. Of the 118 patients enrolled, 103 had normal renal function. On day 1, 64 patients had laboratory-confirmed influenza. Ninety-four (80 %) patients completed 5 days of oseltamivir treatment (32 intravenous only). Sixty-eight and 13 patients reported on-treatment AEs and serious AEs (SAEs), respectively (62 and nine during intravenous dosing, respectively). For 33 and six patients, these AEs and SAEs were considered treatment-related (31 and five during intravenous dosing, respectively); 11 patients had AEs causing treatment withdrawal. Five patients died. Adequate systemic exposure to oseltamivir carboxylate (OC) was achieved at the intravenous doses tested. Oseltamivir-resistant viruses (H275Y) were detected in two patients. In seriously ill, hospitalized patients with/without renal impairment, intravenous oseltamivir was not associated with adverse safety findings at the dosages tested and achieved systemic OC exposures at least as high as the approved oral dose.

miR-126 inhibits proliferation of small cell lung cancer cells by targeting SLC7A5

Despite intensive efforts to improve therapies, small cell lung cancer (SCLC) still has a dismal median survival of 18 months. Since miR-126 is under-expressed in the majority of SCLC tumors, we investigated the effect of miR-126 overexpression on the proliferation and cell cycle distribution of H69 cells. Our results demonstrate that miR-126 inhibits proliferation of H69 cells, by delaying the cells in the G1 phase. Short interfering RNA (siRNA) mediated suppression of SLC7A5, a predicted target of mir-126, has the same effect on H69 cells. We also show for the first time that SLC7A5 is a direct target of miR-126.

Voiding urosonography with second-generation contrast agent versus voiding cystourethrography

Contrast-enhanced voiding urosonography (VUS) is becoming more widely used for the diagnosis of vesicoureteric reflux (VUR). The purpose of this study was to evaluate the sensitivity of VUS using a second-generation ultrasound (US) contrast agent and compare it with standard fluoroscopic voiding cystourethrography (VCUG). A total of 183 children with 366 kidney-ureter units (KUUs) underwent VUS and VCUG in the same session with the same catheterization. VUS was performed after intravesical administration of 1 ml of a second-generation ultrasound contrast agent (UCA; SonoVue, Bracco, Italy). VUR was detected in 140 out of 366 cases (38%); in 89 (24.3%) by both methods, in 37 (10.1%) by VUS only, and in 14 (3.8%) by VCUG only. Although there was considerable agreement in the diagnosis of VUR by VUS and VCUG (κ=0.68, standard error [κ]=0.04), the difference in the detection rate of reflux between VUS and VCUG was significant (p<0.00001). The grade of VUR detected with VUS showed moderate agreement with grading by VCUG. Our findings suggest that contrast-enhanced harmonic VUS using a second-generation contrast agent is superior to VCUG in the detection and grading of VUR, and it should be the method of choice for this clinical indication.

[Infantile acute lobar nephritis]

INTRODUCTION

Acute lobar nephronia is a focal interstitial inflammation of the kidney healing well on conservative therapy.

OBJECTIVE

Authors call attention on this rare pathological entity and emphasize the role of the imaging modalities in making the diagnosis. Short literature review is also given.

PATIENT AND METHODS

An 11 months old babyboy presented with febrile seizure and palpable right flank mass. Abdominal sonography and CT were done.

RESULTS

Urine analysis gave evidence of upper urinary tract infection. Hyperechogenic solid mass in the right kidney was seen on sonography. Diagnosis of infection suspected on sonography has been confirmed by abdominal CT scan and possibility of tumor has been ruled out. Acute lobar nephronia was diagnosed and the patient has been treated successfully with antibiotics.

CONCLUSION

Acute lobar nephronia may mimic both abscess and tumor. Differential diagnosis is very important because treatment of acute lobar nephronia is nonsurgical.

[Multicystic dysplastic kidney: natural history of the affected and the contralateral kidney compared to the normal and solitary kidney]

INTRODUCTION

Complications of multicystic dysplastic kidney are rare, but hypertension and malignant transformation represent real danger.

PATIENTS/METHODS

In a 10-year period, 94 infants (60 boys, 34 girls) with multicystic dysplastic kidney were diagnosed. The data obtained from these patients were compared to 70 children with solitary kidney of which 36 were newborns. In 80 cases (85%) the diagnosis of multicystic dysplastic kidney was already suspected by prenatal sonography.

RESULTS

Abnormalities of the contralateral kidney were found in 15 of the 94 patients (16%). Complete involution of the multicystic dysplastic kidney was observed in 19, and a decrease in size in 42%. In 37 children (39%) the dysplastic kidney has been removed at the age of about 1 year because of no involution. The length of the contralateral kidney, compared to the normal standard was already significantly larger at birth. In newborn babies with unilateral renal agenesia the solitary kidney was also significantly longer.

CONCLUSIONS

Compensatory hypertrophy of single functioning kidneys occurs in utero both in patients with multicystic dysplastic kidney and in those with unilateral renal agenesia. Based on the results of these and previous studies, early nephrectomy cannot be recommended in the newborn period. Surgery remains an option for patients who have no involution at the time of about 1 year of age.

Meconium periorchitis: case report and literature review

Meconium periorchitis (MPO) is an uncommon entity associated with healed meconium peritonitis. The typical presentation is soft hydrocele at birth which becomes harder in weeks as the meconium calcifies. It mimics a scrotal mass, and, without knowledge of this rare disease, this may lead to unnecessary surgery. Both the masses and the calcifications have the tendency to resolve spontaneously without compromising the testicle. Sonographic features together with an abdominal plain film are diagnostic, and visualization of the normal testicle may be helpful in differentiating this tumor-like lesion from scrotal tumors. A case of a meconium periorchitis is reported on and the radiological and histological features are discussed with a literature review on the subject.

Changes of urinary enzyme activity after endoscopic treatment of vesico-ureteric reflux

The urinary enzymes Gamma Glutamyl Transferase (GGT), Alkaline Phosphatase (ALP), Leucine-Arylamidase (LAS), and Dipeptidyl-Peptidase-IV (DPP-IV) were measured before and after endoscopic treatment of vesico-ureteric reflux (VUR) in two groups of twenty children. Ten patients had undergone successful endoscopic corrective surgery for VUR, another 10 patients had unsuccessful endoscopic intervention. After successful treatment the activity of LAS in the urine did not change, but GGT, ALP and DPP-IV activity in the urine was 2-5 times higher than before treatment (P < 0.03 for all three enzymes). Considerable changes of urinary enzyme activity were not observed following unsuccessful endoscopic treatment. Our data and the literature are contradictory. However, this contradiction might be explained by the differences in urine sampling methods. Our patients received the same chemoprophylactic drug at the time of both urine samplings, a point not considered by other researchers. The extent of increase of enzyme activity after endoscopic treatment of VUR did not reach the level that would permit the use of investigated enzymes for screening, because the observed changes did not exceed the limits of the normal range.

[Usefulness of ultrasound in the diagnosis of vesico-ureteral reflux in neonates and infants]

PURPOSE

Postnatal ultrasound (US) findings were assessed in an infant population with primary vesicoureteral reflux (VUR) and the findings of voiding cystourethrography (VCUG) were compared with those of sonography.

MATERIALS AND METHODS

Between 1988 and 1997 55 babies (43 boys and 12 girls) with primary VUR were diagnosed. US criteria for suspected VUR included unexplained or transient fullness of the collecting system, pelvic wall thickening and signs of renal dysplasia.

RESULTS

Among 55 patients reflux was unilateral in 32 cases, and bilateral in 23 patients, altogether 78 refluxing units were investigated. VUR Grade III-V, were detected in 62 units (79%). At least one US anomaly was present in 66 units (85%). No ultrasound anomaly was found in 12 renal units (15%). In 34 cases (44%) conservative treatment was performed, 40 renal units (51%) underwent ureteric reimplantation, and in 4 (5%) cases nephrectomy was carried out.

CONCLUSIONS

The correct detection and grading of reflux is not reliable by sonography, although with careful US examination of the neonatal urinary tract in 85% of VUR cases at least one sonographic abnormality has been found. However, the US negative group, (15%) showed severe reflux on VCUG in a few cases. Therefore, all neonates with ultrasound pathology of unknown origin detected prenatal or postnatal, should undergo VCUG to exclude VUR.

[Changes in urinary enzyme activity following silicon therapy of vesico-ureteral reflux]

The urinary enzymes Gamma Glutamyl Transferase (GGT), Alkaline Phosphatase (ALP), Leucine-Arylamidase (LAS) and Dipeptidyl-Peptidase-IV (DPP-IV) were measured before and after endoscopic treatment of vesico-ureteric reflux (VUR) in two groups of twenty children's. Ten patients had undergone successful endoscopic corrective surgery for VUR, another 10 patients had unsuccessful endoscopic intervention. After successful treatment the activity of LAS in the urine did not change, but that of GGT, ALP and DDP-IV activity in the urine was 2-5 times higher than before treatment (P < 0.03 for all three enzymes). Considerable changes of urinary enzymes' activity were not observed following unsuccessful endoscopic treatment. Our data and the literature are contradictory. However this contradiction might be explained by the differences in urine sampling methods. Our patients received the same chemoprofilactic drug at the time of both urine sampling, a point not considered by other researchers. The extent of increase of enzyme activity after endoscopic treatment of VUR did not reach the level that would permit the use of investigated enzymes for screening, because the observed changes did not exceed the limits of the normal range.

[Diagnosis of neonatal liver hemangioma]

The hepatic hemangiomas of infancy are rare, benign vascular tumours, differentiated in their morphologic and clinical appearances. They may manifest either as asymptomatic liver masses, or with the potentially fatal complication of congestive heart failure. They can be large in infancy, act as arteriovenous fistulas and may result in massive arteriovenous shunt. Multiple imaging modalities have been employed in the diagnosis, including ultrasonography (US), computed tomography (CT), radionuclide studies, angiography, magnetic resonance (MR) imaging. Generally the US, Doppler and CT appearances of hepatic hemangiomas may be diagnostic. Biopsy in often needed for diagnosis, especially if classic signs and symptoms are lacking. The diagnostic possibilities and difficulties in three patients are discussed. Different US images were present in all three cases, with atypical CT appearance in one. Doppler signals were lacking in two cases. Sonographic appearance of infantile hepatic hemangioma is variable, non-specific, but Doppler US is useful as a non-invasive method in the follow-up of hemangiomas.