1099H
Fig. 16.4 This 3-year-old child was
brought to the dental surgery with
spontaneous bleeding from his gums. He
had recently had several nosebleeds and
had become very lethargic. His skin and
mucosa were very pale. Haematological
investigation showed acute lymphocytic
leukaemia.1100H
Fig. 16.5 Oral appearance of a patient
with acute myeloid leukaemia, with
infiltration of the gingivae and
spontaneous bleeding. This oral
presentation and type of leukaemia is less
common than the lymphocytic type
shown in 1101HFig. 16.4. (Courtesy of Wolfe
Publishing.).16.4 RESPIRATORY DISORDERS
16.4.0 Introduction
There are age-related disease patterns as far as the respiratory system is concerned;
these patterns are also affected by sex, race, season of the year, geography, and
environmental and socio-economic conditions. For example, the relatively short
eustachian tube in infants and young children allows easy access to ascending
infections from the pharynx. Cystic fibrosis largely affects Caucasians, whereas lung
infections and infarctions associated with sickle-cell disease occur almost exclusively
in Black children. Seasonal variation in the incidence of respiratory tract infections
and asthma are quite marked and certain infections have a well-defined geographical
distribution. The frequency of bronchitis may not be very different between socio-
economic groups, but the severity may reflect differences in nutritional status and
perhaps the availability of medical care.
16.4.1 Asthma
Asthma is a diffuse obstructive lung disease that causes breathlessness, coughing, and
wheezing. It is associated with hyperreactivity of the airways to a variety of stimuli
and a high degree of reversibility of the obstructive process. Asthma is a leading
cause of chronic illness in childhood. Prevalence data are conflicting, but at least 10%
of children will, at some time, have signs and symptoms compatible with a diagnosis
of asthma. There is mounting recent evidence to suggest that the prevalence is
increasing. Before puberty approximately twice as many boys as girls will suffer from
asthma, thereafter, the sex incidence is similar. About half the children who are