Analysis of chimerism during the early period after allogeneic peripheral stem cell transplantation

As there are few reports on early evaluation of chimerism, we assessed fluorescence short tandem repeats (STR) by polymerase chain reaction (PCR) assays to analyse donor and recipient characteristics at early time points after peripheral stem cell transplantation (PBSCT). Peripheral blood of 13 patients was analysed in 1- to 2-day intervals starting from the day of PBSCT. Donor and recipient allelic patterns were determined by a commercially available multiplex STR assay that simultaneously evaluates four or five gene loci. Mixed chimerism appeared in all patients during days 1-9 after transplantation and preceded haematologic engraftment for 3-12 days. Even patients without myeloablative conditioning therapy (n=4) revealed donor allelic patterns within 1-5 days. Nine patients changed during the following days to a complete donor allelic pattern and had an uncomplicated post-transplant disease course. Four patients did not consistently retain complete donor chimerism; two of them relapsed within the next 3 months, one died from septicemia within 7 days, and the fourth, transplanted for aplastic anaemia, is still in complete remission. Overall, STR analysis using a simple and comparatively cheap multiplex system permits the detection of chimerism very early after transplantation and may provide relevant information that correlates with the clinical follow-up.     

Diagnostic potential of neutrophil elastase inhibitor complex in the routine care of critically ill newborn infants

It has been suggested that determination of the neutrophil elastase α1-proteinase inhibitor complex (E-α1PI) improves the diagnosis of bacterial infection in newborns. We evaluated the use of E-α1PI measurements in 143 newborns, consecutively admitted to a tertiary intensive care unit, employing a new random access assay and a sampling procedure that minimises post-collection artefacts. The 95% range for non-infected newborns was 20–110 μg/l up to the 5th day of life and 20–85 μg/l thereafter. The sensitivity as to the diagnosis of culture-proven bloodstream infection was 80% for E-α1PI, 86% for the immature to total neutrophil ratio, 64% for C-reactive protein and 37% for the total white blood cell count. The corresponding specificity amounted to 97%, 85%, 85% and 86%, respectively. E-α1PI increases preceded elevations of C-reactive protein by 18 h. Like C-reactive protein, E-α1PI levels did not distinguish between bloodstream infection and non-bacterial inflammatory responses. Results of E-α1PI became available within 1 h of collection and usually 2–3 h before manual leucocyte counts. Conclusion Determination of neutrophil elastase α1-proteinase inhibitor levels yields diagnostic advantages comparable to those of manual differential counts but provide faster turnaround times. Received: 16 February 2000 / Accepted: 8 March 2000     

Effects of protein kinase C activators on phorbol ester-sensitive and - resistant EL4 thymoma cells

Phorbol ester-sensitive EL4 murine thymoma cells respond to phorbol 12- myristate 13-acetate with activation of ERK mitogen-activated protein kinases, synthesis of interleukin-2, and death, whereas phorbol ester- resistant variants of this cell line do not exhibit these responses. Additional aspects of the resistant phenotype were examined, using a newly-established resistant cell line. Phorbol ester induced morphological changes, ERK activation, calcium-dependent activation of the c-Jun N-terminal kinase (JNK), interleukin-2 synthesis, and growth inhibition in sensitive but not resistant cells. A series of protein kinase C activators caused membrane translocation of protein kinase C's (PKCs) alpha, eta, and theta in both cell lines. While PKC eta was expressed at higher levels in sensitive than in resistant cells, overexpression of PKC eta did not restore phorbol ester-induced ERK activation to resistant cells. In sensitive cells, PKC activators had similar effects on cell viability and ERK activation, but differed in their abilities to induce JNK activation and interleukin-2 synthesis. PD 098059, an inhibitor of the mitogen activated protein (MAP)/ERK kinase kinase MEK, partially inhibited ERK activation and completely blocked phorbol ester-induced cell death in sensitive cells. Thus MEK and/or ERK activation, but not JNK activation or interleukin-2 synthesis, appears to be required for phorbol ester-induced toxicity. Alterations in phorbol ester response pathways, rather than altered expression of PKC isoforms, appear to confer phorbol ester resistance to EL4 cells.      

Retrobulbar hydatid cyst: Assessment of two cases

A 54-year-old man with a unilocular hydatid cyst within the infero-posterior angle of the orbit and a 6-year-old male child with a unilocular hydatid cyst within the supero-medial angle of the orbit are presented. The retrobulbar cysts were diagnosed with computed tomography and ultrasonography and were treated after serologic confirmation.     

Mycobacterial infection in an inner city children's hospital

Childhood tuberculosis is perceived by many as a disease of the past. Experience in a children's hospital serving a deprived population suggested that tuberculosis and other mycobacterial infections were not declining in clinical practice. Fifty three tuberculous and 11 atypical mycobacterial infections were identified between 1978 and 1992. There was no decline in tuberculosis and nine of the 11 atypical infections occurred in the last five years. Altogether 40% of cases of tuberculosis were in non-Asian children; 32% had arrived in the UK or visited family overseas in the previous year; and 38% had a history of tuberculosis contact, usually a close adult relative. Nationally, the previous decline in tuberculosis in all ages has reversed. In the local health districts in London's east end, childhood tuberculosis has also stopped declining and seems to be increasing. It is regrettable that BCG vaccination has been abolished by some districts in the UK, against current recommendations. Childhood tuberculosis is still common in the practice described here, including among children who do not fall into conventionally recognised high risk groups. Inner city dwellers and junior doctors are both highly mobile populations, adding to the risk that paediatricians, particularly those in training, may encounter tuberculosis with little or no previous experience of the condition.     

Protein nutrition, faecal flora and iron metabolism: the role of milk-based formulae

This paper explores the role of milk-based formulae in achieving four aspects of nutritional health in infants and toddlers: in the suckling, to mimic the amino acid metabolism and the faecal flora of a breast-fed baby; in the weanling, to achieve adequate protein intakes in later infancy and beyond and to achieve satisfactory haemoglobin concentrations in the early toddler years. Milk-based formulae have two roles in infant nutrition: as so-called breast milk substitutes and as a safety net during the weaning period; the latter role may be the more important.     

Malnutrition as a prognostic factor in lymphoblastic leukaemia: a multivariate analysis

One hundred and twenty eight Brazilian children with lymphoblastic leukaemia were intensively treated with a Berlin-Frankfurt-Munich based protocol. More children had a white cell count above 50 x 10(9)/l (31%) then observed in developed countries. After a median follow up of 31 months (11-58 months), the estimated probability of relapse free survival was 41% (7%) for the whole group. After adjustment in the Cox's multivariate model, malnutrition was the most significant adverse factor affecting duration of complete remission. Age above 8 years and high peripheral white cell count were also significant adverse factors. Among the nutritional indices, the height for age and weight for age z scores were both significant, whether the cut off points of z-2 or z = -1.28 were chosen to define malnutrition. A strong statistical association between the two indices was found; the contribution of height for age z score to the prediction of relapse free survival was more significant. Children with height for age z score < -2 had a relapse risk of 8.2 (95% confidence interval 3.1 to 21.9) relative to children with z score > -2. The results of this study suggest that socioeconomic and nutritional factors should be considered in the prognostic evaluation of children with leukaemia in developing countries.     

Guanosine triphosphate cyclohydrolase I deficiency: a rare cause of hyperphenylalaninemia

Tetrahydrobiopterin (BH4) deficiencies are a heterogeneous group of disorders caused by a defect in two of the three enzymes involved in its biosynthesis or in the two recycling enzymes. Except for the deficiency of dehydratase, an enzyme catalyzing a reaction in the recycling pathway, all other variants of BH4 deficiency are characterized by developmental delay, progressive neurological deterioration, hypokinesis, drooling, swallowing difficulty, truncal hypotonia, increased limb tone, myoclonus and brisk deep tendon reflexes. A deficiency of guanosine triphosphate cyclohydrolase I (GTPCH), the first enzyme in the biosynthetic pathway of BH4, is described in a 14-month-old male infant with hyperphenylalaninemia, developmental delay, hypertonia of the extremities, seizures, feeding difficulties, and vomiting. Urinary pteridine screening revealed very low levels of neopterin and biopterin which was highly suggestive of GTPCH deficiency. Low cerebrospinal fluid concentrations of 5-hydroxyindoleacetic acid (5HIAA) and homovanillic acid concentrations, together with no detectable neopterin and decreased concentrations of biopterin and folate, agreed with the diagnosis of GTPCH deficiency. Subsequently measured neopterin and biopterin synthesis in cytokine-stimulated skin fibroblasts confirmed GTPCH deficiency, albeit indirectly. The patient showed marked improvement on a low-protein low-phenylalanine diet with neurotransmitter precursor administration. The favorable outcome in this patient clearly shows that not only newborns with elevated phenylalanine levels but also older children with neurological signs and symptoms should be screened for a BH4 deficiency in order to have maximum benefit of the treatment.