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Objective: Although transient hyperphosphatasemia (TH) has been well known for decades, its etiology and pathophysiology remain unclear. We aimed to study the clinical characteristics of children diagnosed with TH compared to older studies in order to expand our knowledge and understanding of this condition and to try and find a subgroup of children who are more prone to develop TH., Methods: We retrospectively studied 60 children diagnosed at Maccabi Health Services and Bnai Zion Medical Center, Haifa, Israel with TH between the years 2003-08. One hundred and twenty-two children matched by age, gender and presenting symptoms served as the control group. The patients were divided into four subgroups by their presenting symptoms: infectious disease 33%, failure to thrive 28%, diarrhea 15% and other 23%. The Hydragel 7 ISO-PAL and Hydragel 15 ISO-PAL kits were used for the identification and quantification of ALP isoenzymes in human serum., Results: The ALP levels of the study group were 805-8619 U\L (mean 2311 U\L), without differences between the subgroups. The mean duration of TH was 12 weeks. ALP isoenzymes levels were measured in one-third of the patients, and showed that the bone isoenzyme was elevated in most. Forty-three (71%) subjects were diagnosed in the second half of the calendar year., Conclusions: We could not establish an etiological explanation for TH. We presume that it is a complex mechanism in which different stimuli led to upregulation of the enzyme., (© 2010 The Authors. Pediatrics International © 2010 Japan Pediatric Society.)

The objective was to investigate the changes occurring in the activities of the enzymes lactate dehydrogenase (LDH), alkaline phosphatase (ALP) and aspartate aminotransferase (AST) in sheep and goat milk as a result of subclinical intramammary infections (IMI) and to evaluate the use of these enzymes for the diagnosis of subclinical IMI in dairy sheep and goats. A total of 206 samples of sheep milk and 162 samples of goat milk, obtained from equal udder halves, were used in the study. For each species they were divided into two groups: a no-infection group and a subclinical infection group. Activities of LDH, ALP and AST were significantly higher in the subclinical infection group than in the no-infection group (P<0.05) in both sheep (LDH: 350.42+/-11.25 v. 120.91+/-4.41; ALP: 2773.43+/-105.18 v. 2189+/-94.24; AST: 29.57+/-0.74 v. 17.32+/-0.46) and goats (LDH: 354.07+/-13.33 v. 103.79+/-3.75; ALP: 311.13+/-25.74 v. 137.24+/-19.62; AST: 27.59+/-6.42 v. 15.87+/-0.45). The activity of LDH was identified as indicator for subclinical IMI in both sheep and goats. The optimum cut-off values for LDH activity, offering the highest diagnostic sensitivity (DSn) and diagnostic specificity (DSp), determined by receiver operating characteristic (ROC) analysis, were at 197 U/l, 185 U/l and 197 U/l for sheep, goats and both species, respectively. DSn for sheep, goats and both species at these cut-off values was 92.8%, 98.2% and 94.0%, whereas DSp was 95.4%, 96.3% and 96.3%, respectively. It was concluded that the determination of LDH activity in milk serum is a sensitive and reliable method for the detection of subclinical IMI in dairy sheep and goats.

In patients suffering from acute bacterial infections specific autoantibodies of the immunoglobulin class G (IgG), directed against intestinal alkaline phosphatase (IAP), are transiently expressed in high titer. The epitopes on IAP which are recognized by these IAP auto-antibodies were investigated using chemical and enzymatic cleavage, followed by two-dimensional electrophoresis and immunoblotting of the fragments. Immunoreactive and nonreactive cleavage fragments were isolated and N-terminally sequenced. An epitope map was constructed by means of sequencing data, relative molecular mass of the fragments, and specific cleavage sites. To evaluate linear epitopes, the overlapping region of the immunoreactive fragments (amino acids 204-484 of the primary structure of IAP) was further analyzed by simultaneous synthesis of 95 peptides on an activated membrane. Four immunoreactive regions were revealed by immunodetection with IAP autoantibody-positive sera. Nine peptides comprising these regions were synthesized quantitatively and coupled to CH-Sepharose. However, specific IAP autoantibodies could not be isolated. This result indicated the absence of continuous epitopes at least in the analyzed region of the molecule. Binding studies with an IAP cleavage fragment suggested a discontinuous epitope involving amino acids 334-371. The results are indicative of an antigen-driven mechanism for the production of IAP autoantibodies initiated and maintained by self.

An individual with repeated bacterial infections, eczema, hyperimmunoglobulin E, and a primary deficiency of leucocyte alkaline phosphatase is described. The Lap-deficient neutrophils from this patient had marginally deficient bactericidal activity particularly when challenged with high ratios of bacteria per neutrophil. Leucotactic, metabolic and morphologic features of the neutrophils from the patient were normal. Evidence is presented which contrasts this patient's condition with previously described primary or secondary deficiencies of LAP.

The leucocyte alkaline phosphatase (LAP) score was estimated in healthy and infected neonates. A leucocyte band count was also done simultaneously. The infected group showed a significant (P < 0.001) decrease in the LAP score and a significant (P < 0.001) increase in the band count. These findings are discussed.

Clinical and biochemical features of transient hyperphosphatasemia of infancy and early childhood are reviewed in 21 patients we have studied and in a further 93 cases reported in the literature. The diagnosis is suggested by the finding of an increased activity of alkaline phosphatase (EC 3.1.3.1) in plasma, typically more than fivefold the adult upper reference limit, in a child under five years of age, without evidence of liver or bone disease. The condition is confirmed by the presence of a characteristic pattern of alkaline phosphatase isoenzymes and by the normalization of the enzyme's activity in plasma within approximately three months. The etiology of the condition and possible mechanisms of the enzyme increase are discussed.