BRITISH MEDICAL JOURNAL VOLUME 285 3 juLY 1982 23 inflamed mucosa with no parasites. Sections from the mucosa of ileum and caecum and the rectal biopsy specimen, trypsinised and stained with antisera to immunoglobulins, kappa and lambda chains, and IgA secretor piece, using the immunoperoxidase method, showed similar numbers and distributions of positive lymphocytes to those in normal controls. Peripheral lympho-cyte subpopulations showed normal T-and B-cell proportions with a normal distribution of surface immunoglobulin classes on B cells. T-cell transformation was normal after stimulation by phytohaemagglutinin. Serum M~~~~ Caecal epithelial microvillar surface showing cryptosporidium schizont containing merozoites. X 18 000 (original magnification). IgG concentrations and complement components C3 and C4 were normal, serum IgA was low (400 mg/l; normal 860-3700 mg/l), IgM low (510 mg/l; normal, 700-3700 mg/l), and IgE raised (205 U/ml using paper radio-immunosorbent test; normal adult mean 122 U/ml). Comment The ultrastructure of these organisms was sufficiently distinctive for a diagnosis to be made on morphology alone, and in our case the inflammation within the ileal and caecal mucosa was probably due to the organism. The patient's immune state, with marginally decreased concentrations of serum IgA and IgM, though not fulfilling any of the recognised criteria for general or selective immune deficiency, suggests an element of unexplained immune paresis. The virus-like particles found in the nucleus and cytoplasm of mucosal epithelial cells by Bird and Smith5 were not found in our case. Increased awareness of cryptosporidial enterocolitis may increase the frequency of detection of such cases. We thank Mr J B Self for clinical information; Dr D S Ridley, Hospital for Tropical Diseases, London, for help in the initial diagnosis; Dr H Sewell, Mr A Willox, and the immunopathology department Leicester Royal Infirmary; and Mrs G Holmes for typing the manuscript. Meisel JL, Perera DR, Meligro C, Rubin CE. Overwhelming watery diarrhoea associated with a cryptosporidium in an immunosuppressed patient. Gastroenterology 1976 ;70 :1156-60. 2 Lasser KH, Lewin KJ, Ryning FW. Cryptosporidial enteritis in a patient with congenital hypogammaglobulinaemia. Hum Pathol 1979 ;1O :234-40. 3Nime FA, Burek DJ, Page DL, Holscher MA, Yardley JH. Acute entero-colitis in a human being infected with protozoan cryptosporidium. Gastroenterology 1976;70 :592-8. 4 Royal College of Physicians of London. Immunodeficiency and crypto-sporidiosis. Leicester Royal Infirmary, Leicester LE2 7LX A FLETCHER, MB, cHB, lecturer and honorary senior registrar, department of pathology T A SIMS, FIMLS, chief medical laboratory scientific officer, department of electron microscopy I C TALBOT, MD, MRCPATH, senior lecturer and honorary consultant pathologist, department of pathology Frequency of swallowing in duodenal ulceration and hiatus hernia There is wide individual variation in the rate of spontaneous swallowing. In the absence of food up to 5 ml of air...