Amniotic fluid acetylcholinesterase measurements: comparing immunochemical and polyacrylamide gel techniques

In the present study, a recently reported immunochemical technique for measuring acetylcholinesterase (AChE) in amniotic fluid utilizing the 4F19 antibody was compared with the widely utilized polyacrylamide gel technique to determine whether the immunochemical assay provided an advantage in separating unaffected pregnancies from those associated with open spina bifida (OSB) and open ventral wall defects (OVWD). The study included (1) 73 amniotic fluid samples from unaffected pregnancies [alpha-fetoprotein (AFP) less than 2 MoM] with no visible gel AChE band, (2) nine bloodstained samples from unaffected pregnancies (AFP 2.2-4.0 MoM) with visible gel AChE bands, (3) 18 samples associated with OSB (AFP 2.2-7.0 MoM) with visible gel AChE bands, and (4) 20 samples associated with OVWD (AFP 3.2-53.5 MoM) with visible gel AChE bands. The immunochemical assay produced ranges of measurements in the four respective categories as follows: (1) 2-60 arbitrary units (AU): (2) 14-69 AU, (3) 61-593 AU, and (4) 22-476 AU. Eight of the nine unaffected pregnancies with visible gel AChE bands had immunochemical measurements below the highest measurement for the samples with no visible AChE band (60 AU), as did five out of 20 OVWD pregnancies. Two of the OSB cases had values of 61 and 62 AU. These data indicate that the 4F19 specific monoclonal antibody to AChE is capable of distinguishing unaffected from affected pregnancies with reasonable reliability but that more work needs to be done to establish the extent of overlap between the unaffected and affected populations.     

The diagnosis and treatment of midline neck masses in children

Frustration in differentiating before operation among the various causes of midline neck masses stimulated us to review the clinical, operative, and pathologic findings in 176 children hospitalized for a midline cervical lump. The preoperative diagnosis was correct in 61% of these cases, the surgeon's postoperative diagnosis was correct in 83%, and the pathologist's diagnosis was correct in 98%. Only recurrence following prior excision and persistent sinus following drainage of a midline cyst were pathognomonic preoperative indicators of a thyroglossal duct cyst; these findings were present in only 6% of the cases. The age of the child, a history of inflammation or of fluctuation in size, the dimensions of the mass, and the relationship of the mass to the hyoid were useful in differentiating among groups of children with a thyroglossal cyst, an epidermoid cyst, or an enlarged perihyoid lymph node. The duration of the presence of the mass and its movement with swallowing were not helpful. Using the preoperatively recorded historical and physical findings in these children with a known cause for their midline neck mass and applying Bayes' theorem, one can only achieve a correct preoperative diagnosis with an 80% accuracy based on the best available data. Consequently, additional information obtained at surgical exploration is needed to establish a secure diagnosis and to ensure appropriate treatment.     

Is schizophrenia an autoimmune disease? A review

Autoimmunity has been shown to be the basis of an ever-increasing number of human diseases. Schizophrenia shares a number of genetic features with these autoimmune diseases and therefore could be an autoimmune disease itself. Several lines of evidence suggest that overactivity of dopaminergic pathways in some areas of the brain are involved in schizophrenia, but the apparent absence of an increase in dopamine turnover suggests that this hyperactivity could be mediated by a dopamine agonist rather than by dopamine itself. Schizophrenia is reviewed in the light of precedents from the field of autoimmune diseases in which autoantibodies have been shown to be able to interact with, and sometimes stimulate hormone receptors, thereby causing disease.     

Management of pneumothorax in adults with cystic fibrosis.

The histories of 243 adults with cystic fibrosis were reviewed; 46 had experienced one or more spontaneous pneumothoraces (18.9%), and seven had died of this complication. There was a high incidence of recurrence on the same side after conservative management (50%) or intercostal drainage (55.2%). Prolonged intercostal drainage was associated with a high mortality. One-third of patients required surgical treatment. Twenty thoracotomies were performed. Three of these patients died but only two of the 17 survivors had recurrences. Severe airflow obstruction was not a contraindication to surgery. A plan of management for future cases is outlined.     

Primary linitis plastica carcinoma of urinary bladder

Primary linitis plastica type carcinoma of the urinary bladder in a sixty-one-year-old man is described. Only 2 other cases have been reported in the English medical literature.     

Blood selenium values in an adult Auckland population group.

New Zealand top soils are low in selenium with some regional variation. Grain and cereal products are the main source of dietary selenium intake but in New Zealand their content is low due to widespread top soil deficiency. Whole blood levels reported from Oago, 68 +/- 13ng/ml, are a half to one-third of those in North America and also lower than in Auckland residents, 79 +/- 15.7ng/ml. The variation between New Zealanders is due to regional differences in top soil levels and grass content affecting secondary selenium sources such as sheep meat and beef. Regular consumption of selenium rich chicken and fish is associated with a significant increase above average values, but age, sex, smoking, alcohol and the use of oral contraceptives, are unimportant factors.