fully descended during infancy but where orchidopexies had been done after referral as a result of school medical examinations. One of these boys had had two operations for hypospadias and the other, a premature infant, was followed up by one of us (TML) for two years. CommentIt is generally agreed that surgery for undescended testis should be performed by not later than 5 years of age. All but one of our consultant colleagues agreed with this, as did 75% of the general practitioners, yet only 32% of operations were done by the recommended age. Why does this happen and what does it mean?The incidence of undescended testis after the age of 1 year is about 0-8%.1 2 Between infancy and puberty, however, retractility of the testis may make diagnosis difficult; one survey found that 6% of boys between the ages of 5 and 11 appeared to have undescended testes but by the age of 14 this figure had fallen to 0 6%.3 A paediatric surgeon mentioned this problem and said that he was reluctant to operate on boys in whom the diagnosis of undescended testis had not been documented during infancy.Chilvers et al studied the increasing orchidopexy rate over the past 20 years and suggested that surgery on boys with retractile testes could explain the increase. Materials, methods, and resultsUsing laboratory records to identify patients who had haemophilus isolated from the respiratory tract, we conducted a retrospective study of patients' case notes to record the clinical features at the time the specimen was produced. We also recorded bacteriological features of the isolate. Specimens were inoculated on to horse blood agar and heated horse blood agar containing 10 units bacitracin/ml and incubated for 18 hours at 37'C in 7% carbon dioxide. Non-haemolytic haemophilus colonies were identified by typical appearance and the organism confirmed by Gram stain and satellitism with Staphylococcus aureus. Differentiation between H influenzae and H parainfluenzae was achieved by their ability (H parainfluenzae) or failure (H influenzae) to metabolise 8-aminolaevulinic acid.The monthly frequency of isolations of H influenzae and H parainfluenzae, the underlying diagnosis and presenting symptoms, the antibiotic sensitivities, and the frequency of mixed growths were recorded and compared using x2 statistical analysis.There were 689 sputum isolates of H influenzae and 292 of Hparainfluenzae; H influenzae had its peak in March and H parainfluenzae in November. The patients were aged 12-98 years (mean 60 (SD 18) years).The most frequently recorded symptoms associated with isolation of haemophilus were cough (with or without sputum production), dyspnoea, increased sputum purulence, and wheeze, and these varied little among the diagnostic groups of chronic bronchitis, asthma, pneumonia, bronchial carcinoma, and bronchiectasis. There was no difference in the symptoms produced by H influenzae or H parainfluenzae in these groups or in total (figure). In Antibiotic sensitivities were determined in 954 isolates. Ampicillin resistance occurred in 9% of ...

Haemophilus influenzae may cause serious illness in childhood, particularly capsulated Pittman type b organisms.1-3 In the respiratory tract of adults the organism is usually non-capsulated4 and is frequently isolated during acute episodes or exacerbations of respiratory diseases. 5 We have observed that Hparainfluenzae is clinically indistinguishable from non-capsulated H influenzae, suggesting that H parainfluenzae is pathogenic in the respiratory tract of adults.6 Subdivision of H influenzae and H parainfluenzae into biotypes is now possible' 8 and, although this has been performed in childhood illnesses,2 our aim was to determine the epidemiological and clinical value of haemophilus biotyping in adult respiratory diseases. MethodsUsing the laboratory records for 1983 we undertook a retrospective study of the case notes of patients who had had Haemophilus species isolated from the respiratory tract. Sputum specimens were routinely inoculated on to horse blood agar and heated horse blood agar containing 10 units of bacitracin/ml and incubated for 18 hours at 37°C in 7% carbon dioxide. Specimens from patients with suspected anaerobic infections were incubated anaerobically for 48 hours. Non-haemolytic haemophilus organisms were identified by their morphological and colonial appearance and the demonstration of satellitism with Staphylococcus aureus. Differentiation between H influenzae and H parainfluenzae was then achieved by the ability of the organism to metabolise 6-amino laevulinic acid (HP +, HI -). H influenzae and H parainfluenzae were further subdivided into their biotypes by the method of Kilian.7 8The following variables were recorded and analysed: (i) distribution of H influenzae and Hparainfluenzae biotypes in different diagnostic groups; (ii) antibiotic sensitivities, determined by a standard disc susceptibility technique; (iii) frequency of isolation of multiple organisms; (iv) pus cell counts in undiluted sputum-samples being taken from the most purulent part of the specimen-were scored (1-10 cells/high power field (HPF) = 1, [11][12][13][14][15][16][17][18][19][20] After exclusion of 105 isolates from general practice (showing the same biotype distribution as isolates from hospital) and repeat specimens, 574 separate clinical episodes were studied. The diagnostic groups were: chronic bronchitis (n = 201), asthma (n = 63), bronchial carcinoma (n = 107), bronchiectasis (n = 52), pneumonia (n = 38), and "others' (n = 113). In the last group 37% of patients had pre-existing pulmonary disease and 36% had undergone thoracic surgery. All diagnostic groups showed a similar biotype distribution (H influenzae I 15%, II 33%, III 17%, IV 6%, V 4%, VI 2%, VII < 1%; H parainfluenzae 1 6%, 11 1%, III 6%). Recurring clinical episodes were not always attributable to the same biotype, though multiple specimens from a single clinical episode usually (but not invariably) had the same single biotype. Biotype had no bearing on the symptoms recorded in all diagnostic groups, and biotype distribution was similar both ...