ACTN1-related thrombocytopenia: Homozygosity for an ACTN1 variant results in a more severe phenotype

ACTN1-related thrombocytopenia is a rare disorder caused by heterozygous variants in the ACTN1 gene characterized by macrothrombocytopenia and mild bleeding tendency. We describe for the first time two patients affected with ACTN1-RT caused by a homozygous variant in ACTN1 (c.982G>A) with mild heart valve defects unexplained by any other genetic variants investigated by WES. Within the reported family, the homozygous sisters have moderate thrombocytopenia and marked platelet macrocytosis with giant platelets, revealing a more severe haematological phenotype compared to their heterozygous relatives and highlighting a significant effect of allelic burden on platelet size. Moreover, we hypothesize that some ACTN1 variants, especially when present in the homozygous state, may also contribute to the cardiac abnormalities.

Pediatric Presentation of Antiphospholipid Syndrome: A Review of Recent Literature With Estimation of Local Prevalence

We aimed to investigate the epidemiology, the clinical and laboratory characteristics of the pediatric involvement of antiphospholipid syndrome (APS), by performing a review of the current evidence and reviewing local experience in the Northwest Italy. To achieve this, we performed a detailed literature search to identify articles describing clinical and laboratory characteristics of pediatric APS. In concomitance, we conducted a registry-based study collecting data from the Piedmont and Aosta Valley Rare Disease Registry including pediatric patients diagnosed with APS in the last 11 years. The literature review led to inclusion of six articles with a total of 386 pediatric patients (65% females, 50% with systemic lupus erythematosus (SLE) as concomitant diagnosis). Rates of venous and arterial thrombosis were 57 and 35%, respectively. "Extra-criteria manifestations" included mostly hematologic and neurologic involvement. Almost one-quarter of patients (19%) reported recurrent events and 13% manifested as catastrophic APS. A total of 17 pediatric patients (mean age 15.1 ± 2.8, 76% female) developed APS in the Northwest of Italy. In 29% of cases, SLE was a concomitant diagnosis. Deep vein thrombosis was the most frequent manifestation (28%) followed by catastrophic APS (6%). The estimated prevalence of pediatric APS in Piedmont and Aosta Valley Region is 2.5/100,000 people, whereas the estimated annual incidence is 0.2/100,000 inhabitants. In conclusion, clinical manifestations of pediatric APS seem to be more severe and with a high prevalence of noncriteria manifestations. International efforts are needed to better characterize this condition and to develop new specific diagnostic criteria to avoid missed/delayed diagnosis in children with APS.

Successful use of antihistamines in severe hypereosinophilia

Eosinophilia is common in childhood, and in most cases it is mild and of limited clinical relevance, being often secondary to allergy or infections. In rare cases, eosinophilia may be idiopathic or related to neoplastic aetiology. When severe and protracted, it can cause potentially irreversible organ or system damage, whose prevention is the first priority in the clinical management of hypereosinophilia. We describe the case of a patient with very severe eosinophilia, in whom antihistamines proved to be effective and safe in contributing to the eosinophil count normalization, thus avoiding the use of steroids until the hypothesis of an underlying neoplastic disorder was reasonably excluded.

Adrenal axis function after high-dose steroid therapy for childhood acute lymphoblastic leukemia

BACKGROUND

A 4-week course of high-dose glucocorticoids may cause prolonged adrenal suppression even after a 9-day tapering phase. In this study, adrenal function and signs and symptoms of adrenal insufficiency were prospectively assessed in children with acute lymphoblastic leukemia (ALL) after induction treatment including high-dose prednisone (PDN) or dexamethasone (DXM).

PROCEDURES

Sixty-four children with ALL, treated according to the AIEOP ALL 2000 Study protocol, underwent low dose ACTH (LD-ACTH) stimulation 24 hr after the last tapered steroid dose. In those with impaired cortisol response, additional LD ACTH tests were performed every 1-2 weeks until cortisol levels normalized. Signs and symptoms of adrenal insufficiency were recorded during the observation period.

RESULTS

All patients had normal basal cortisol values at diagnosis. Twenty-four hours after last glucocorticoid dose, morning cortisol was reduced in 40/64 (62.5%) patients. LD-ACTH testing showed adrenal suppression in 52/64 (81.5%) patients. At the following ACTH test 7-14 days later, morning cortisol values were reduced in 8/52 (15.4%) patients and response to the test was impaired in 12/52 (23%). Adrenal function completely recovered in all patients within 10 weeks. No difference was found between patients treated with PDN or DXM. Almost 35% of children with impaired cortisol values at the first test developed signs or symptoms of adrenal insufficiency. One child developed a severe adrenal crisis during adrenal suppression.

CONCLUSIONS

High-dose glucocorticoid therapy in ALL children may cause prolonged adrenal suppression and related clinical symptoms. Laboratory monitoring of cortisol levels and steroid coverage during stress episodes may be indicated.

Splenectomy in children with chronic ITP: long-term efficacy and relation between its outcome and responses to previous treatments

This retrospective study was conducted to determine whether the response to splenectomy is related to the response to previous treatments. We examined the records of 90 children splenectomized for chronic ITP. Platelet counts were constantly>50x10(9)/L in 68 patients (75%). An improvement in the quality of life was observed in 79 (85%). The success of splenectomy was strongly correlated with a good response to previous treatment. A negative response to any of the prior treatments had no predictive value. This finding is relevant when elective splenectomy is considered as a treatment option.

Steroid withdrawal syndrome during steroid tapering in childhood acute lymphoblastic leukemia: a controlled study comparing prednisone versus dexamethasone in induction phase

Children with acute lymphoblastic leukemia (ALL) receive as part of induction therapy a 4-week course of high-dose glucocorticoid, which is either abruptly discontinued or shortly tapered. The aim of this study was to evaluate the signs and symptoms of steroid withdrawal syndrome and performance status (according to Lansky scale) during the 9-day tapering period and 1 week after withdrawal of the steroid in 63 children randomly allocated to receive prednisone or dexamethasone as part of induction treatment according the AIEOP ALL 2000 protocol. Twenty of 28 (75%) patients on dexamethasone versus 18 of 35 (51.4%) on prednisone (P < 0.05) developed at least one steroid withdrawal symptom during the study period. Three or more symptoms were observed in 39.3% (11/28) of the dexamethasone group and 8.6% (3/35) of the prednisone group (P < 0.05). Dexamethasone patients developed clinical signs earlier (within 3 days from the steroid tapering) than symptomatic prednisone patients. In the prednisone group, the symptoms were less severe and the performance status was higher (P < 0.05). Steroid withdrawal morbidity in ALL children during induction is a frequent and clinically relevant complaint. A more gradual (for dexamethasone) or a more prolonged (for prednisone) tapering might be suggested.

[Convulsions during treatment of acute lymphoblastic leukemia in children]

BACKGROUND

The prevalence of seizures in children with acute lymphoblastic leukemia (ALL) varies between 3 and 13% depending on the various studies, whereas it is 1% in the general population aged under 15 years etiopathogenesis and outcome of seizures in children during treatment for ALL.

METHODS

A retrospective study was carried out in 204 children with a consecutive diagnosis of ALL, 89 females and 115 males, aged between 5 months and 17 years and 11 months, diagnosed between 15-4-1988 and 15-4-1998, and treated at the Division of Pediatric Oncology and Pediatric Hematology of Turin University using three successive generations of AIEOP protocols 88 (48 cases), 91 (86 cases) and 95 (70 cases). Observation of the patients in the study ended on 30-9-1998. The criteria for eligibility were those stated in the respective protocols. Seizures were classified using the international classification; the diagnosis was made if a doctor, a nurse or a reliable relative witnessed the event with confirmation by the consultant neurologist.

RESULTS

Twelve out of 204 (5.8%) patients in this series presented seizures: 2 out of 48 cases using protocol 88 (4.1%), 6 out of 86 cases using protocol 91 (6.9%) and 4 out of 70 cases using protocol 95 (5.7%). None of the patients had critical episodes or other significant neurological pathologies prior to the onset of ALL, nor had they been affected by leukemic meningosis or undergone cranial radiotherapy. When evaluating the possible etiology, the authors noted that, except for one case of febrile convulsion, the seizures in the remaining patients could be attributed to the toxicity of chemotherapy. With regard to the evolution of seizures, only one patient died, whereas the others showed no neurologic sequelae.

CONCLUSIONS

The frequency of seizures in children receiving treatment for ALL in the series analysed here is in line with that reported in the literature. Neurotoxicity caused by chemotherapy appears to be the main etiopathogenetic factor.

Use of recombinant granulocyte colony-stimulating factor in Fanconi's anemia

BACKGROUND AND OBJECTIVE

Granulocyte colony-stimulating factor (G-CSF) has been shown to improve the neutropenic status of patients with bone marrow failure. The side effects in prolonged treatment still need to be determined.

DESIGN AND METHODS

We have studied the efficacy and the long-term side effects of G-CSF in four patients with Fanconi's anemia and severe neutropenia.

RESULTS

Three patients responded with an increase in their absolute neutrophil count; neither improvement in platelet count and hemoglobin concentration nor effect on transfusion requirements was seen. CFU-GM and BFU-E were undetectable before, during and after treatment. Responders showed an important reduction in number and severity of infections, with a marked improvement of clinical status. The fourth patient developed acute myeloid leukemia after 4 weeks of G-CSF treatment. During maintenance, one patient was treated with G-CSF for 18 months, until she received bone marrow transplantation, without presenting side effects. In the second responding patient G-CSF treatment was stopped because of appearance of immature cells in peripheral blood and myeloid blasts in bone marrow. The third responding patient presented immature peripheral myeloid cells during the third year of G-CSF treatment: disappearance of immature cells was observed after G-CSF reduction. In two cases FISH analysis revealed monosomy 7 after G-CSF treatment.

INTERPRETATION AND CONCLUSIONS

G-CSF use results in an improvement of clinical status, but long term administration may cause adverse experiences and requires a close hematological monitoring.

A newly-characterized alpha-thalassaemia-1 deletion removes the entire alpha-like globin gene cluster in an Italian family

We describe a new deletional form of alpha thalassaemia which encompasses the entire alpha-like globin gene cluster in a 15-year-old boy of Southern Italian descent. The deletion removes approximately 31 kb, the 5'-end point is located approximately 4 kb upstream of the xi gene, while the 3'-end point maps between the alpha 1- and theta 1-globin genes. The interaction of this deletion with the common-alpha 3.7 form gives origin to a classical form of haemoglobin (Hb) H disease in the propositus of this study. Deletional forms of xi alpha-thalassaemia are uncommon in the Mediterranean basin; as for other unusual xi alpha-thalassaemia forms, heterozygotes for this mutation may escape detection in population surveys based on zeta and alpha probes.

RFLPs of the phenylalanine hydroxylase gene in the Italian population

Different mutations of the phenylalanine hydroxylase (PAH) gene leading to phenylketonuria (PKU) have been described associated with specific haplotypes in several European countries. In order to investigate the distribution of DNA haplotypes in Italy, restriction fragment length polymorphism (RFLP) analysis of the PAH gene was performed in nine Italian PKU patients from eight unrelated families, and in the available relatives. The analysis of eight polymorphic sites revealed haplotypes 1 and 6 in association with PKU. This pattern appears to differ from those reported for other European populations. The majority of the 14 PKU subjects studied showed compound heterozygosity for different haplotypes, as observed for other European series. RFLP analysis at the PAH locus allowed us to offer the possibility of prenatal diagnosis to six of the studied families. One prenatal diagnosis was performed and a normal fetus was diagnosed.