Hard metal lung disease: a clinical, histological, ultrastructural and X-ray microanalytical study.

Four employees occupied in hard metal grinding work at the same machine shop developed interstitial lung disease after 2-7 years of working. Open lung biopsies from two of them showed giant cell interstitial pneumonia with bronchiolitis. The multinucleate giant cells were shown by electron microscopy to include both pneumocytes and macrophages. The giant pneumocytes were severely damaged, the endoplasmic reticulum being swollen and the few lamellar bodies being small, and some mitoses were visible in the pneumocytes. No mitoses were found in the giant macrophages. Pulmonary dust particles were studied in situ by scanning transmission electron microscopy and energy-dispersive spectrometry. Cobalt was no longer found in most of the pulmonary hard metal particles, but it was regularly detected in grinding dust particles in air samples studied by scanning electron microscopy and energy-dispersive spectrometry.

Withdrawal of inhaled corticosteroid under cover of nedocromil sodium.

Patients satisfactorily controlled on both an inhaled corticosteroid and a regularly inhaled bronchodilator were randomly allocated to 12 weeks of treatment with either nedocromil sodium (4 mg q.i.d.) or matching placebo. After 3 weeks of treatment, inhaled steroids were abruptly withdrawn. Severity of asthma deteriorated in both groups but more rapidly in the placebo group (p less than 0.05). Lung function tests showed little between-group difference. Nedocromil sodium had greater efficacy than placebo in the control of asthma in patients requiring an inhaled corticosteroid but abrupt corticosteroid withdrawal is not recommended. However, there are some clinical suggestions of the benefits of the combined use of nedocromil sodium and an inhaled corticosteroid.

Spirometric studies in non-smoking, healthy adults.

Reference spirometric values for vital capacity (VC), forced expiratory volume in one second (FEV1), forced vital capacity (FVC), forced expiratory volume in one second as percentage of vital capacity or of forced vital capacity (FEV%), the highest flow during forced inspiration (Vmax insp), the highest forced expiratory flow at 50% vital capacity (Vmax 50%), the highest forced expiratory flow when 75% of vital capacity has been expired (Vmax 25%), Vmax insp/Vmax 50% and peak expiratory flow (PEF) were determined in a series of 296 males and 257 females, 18-65 years old, who have never smoked. Equations were derived using height and age as predictors. The reproducibility was tested.

Treatment of steroid-dependent asthma patients with beclomethasone dipropionate aerosol.

Fifty-two steroid-dependent adults with chronic perennial asthma were transferred to beclomethasone dipropionate aerosol. The tests demonstrated a significant improvement with beclomethasone in terms of the diary score, bronchodilator use, and PEF and FEV1.0 measurements, as compared with the previous period of prednisolone treatment. Before the transfer, 26 of the patients displayed one or more diseases or symptoms which were probably due to systemic steroid medication. Morning cortisol levels, along with the response to tetracosactrin had in all cases returned to normal when tests were carried out 41 days after transfer to beclomethasone dipropionate. In a group of 12 patients with the lowest 11-OHCS basal values, the mean of their 11-OHCS values during prednisolone treatment was as low as 0.14 plus or minus 0.06 mumol/l, but tetracosactrin challenge induced an elevation to a normal level, 0.33 plus or minus 0.13 mumol/l. After 41 days of beclomethasone treatment, the corresponding values were 0.56 plus or minus 0.90 plus or minus 0.28 mumol/l. Thirty-seven patients experienced one or more disturbing symptoms after transfer to beclomethasone. In many cases, the symptoms of allergic rhinitis were troublesome and persistent leading to a sixfold increase in the use of antihistaminic tablets. When the patients had learned to exhale through the nose following beclomethasone inhalation, the use of antihistaminic tablets again diminished to some extent. Moreover, two cases of ulcerative colitis were encountered during the beclomethasone treatment. During a follow-up period of one year, 14 patients were again receiving prednisolone; most often, this was due to worsening of the asthma because of respiratory infections. During the beclomethasone treatment, a continuous significant improvement in PEF was noted after isoprenaline inhalation, suggesting that further benefit may be obtained by the employment of bronchodilator aerosols as an essential part of the treatment.

Arterial to end-tidal CO2 difference in respiratory disease.

The difference in CO2 tension between arterial blood and end-tidal alveolar gas (a-end-tidal)DCO2 was found to correlate fairly well with the VD/VT ratio in 13 healthy subjects and 50 patients with pulmonary diseases (r = 0.74), and to discriminate between healthy subjects and patient groups at least as effectively as did the VD/VT ratio. An increase in breathing frequency from 8 to 32/min, without simultaneous change in alveolar ventilation, was associated with a mean increase in (a-end-tidal) DCO2 of several mmHg in both the healthy subjects and the patient groups. It is concluded that measurement of (a-end-tidal)DCO2 seems to be a clinically useful alternative to measurement of VD/VT ratio for evaluation of the wasted ventilation component, provided that the effect of the breathing frequency on (a-end-tidal) DCO2 is taken into account.

Exercise asthma and disodium cromoglycate.

Exercise-induced asthma (defined as a fall in PEF of at least 25% of the pre-exercise value) was studied in adult patients with uncomplicated asthma. This was found to occur in 22 out of 52 patients. Pre-exercise inhalation of disodium cromoglycate reduced the mean fall in PEF after maximal exercise from 50% of the pre-exercise value to 23% (open assessment in 11 cases). After submaximal exercise for eight minutes the reduction was from 18% to 10% (double-blind crossover study in 28 cases). It is concluded that disodium cromoglycate partly inhibits the increase of airways resistance after exercise in asthmatic patients.