see tuberculosis.
The weight loss and wasting associated with tuberculosis before treatment was available led to the disease’s popular name of consumption. Enlargement of the glands in the neck, formerly called scrofula, was known also as the ‘king’s evil’ from the supersition that a touch of the royal hand could cure the condition. Lupus vulgaris (see under LUPUS) is another of the skin manifestations of the disease.
The typical pathological change in tuberculosis involves the formation of clusters of cells called granulomas (see GRANULOMA) with death of the cells in the centre producing CASEATION.
It is estimated that there are 7–8 million new cases of tuberculosis worldwide each year, with 2–3 million deaths. The incidence of tuberculosis in developed countries has shown a steady decline throughout the 20th century, mainly as a result of improved nutrition and social conditions and accelerated by the development of antituberculous chemotherapy in the 1940s. Since the mid-1980s the decline has stopped, and incidence has even started to rise again in inner-city areas. In 2002, 7,239 cases of tuberculosis were noti?ed in the UK compared with 6,442 a decade earlier; more than 390 deaths in 2003 were attributed to the disease. Factors involved in this rise are immigration from higher-prevalence areas, poorer social conditions and homelessness in some urban centres and the association with HIV infection and drug abuse. The incidence of tuberculosis is also rising in many developing countries because of the emergence of resistant strains of the tubercle bacillus (see below). In the UK recently there have been serious outbreaks in a handful of urban-based schools.... tuberculosis
Static lung volumes and capacities can be measured: these include vital capacity – the maximum volume of air that can be exhaled slowly and completely after a maximum deep breath; forced vital capacity is a similar manoeuvre using maximal forceful exhalation and can be measured along with expiratory ?ow rates using simple spirometry; total lung capacity is the total volume of air in the chest after a deep breath in; functional residual capacity is the volume of air in the lungs at the end of a normal expiration, with all respiratory muscles relaxed.
Dynamic lung volumes and ?ow rates re?ect the state of the airways. The forced expiratory volume (FEV) is the amount of air forcefully exhaled during the ?rst second after a full breath – it normally accounts for over 75 per cent of the vital capacity. Maximal voluntary ventilation is calculated by asking the patient to breathe as deeply and quickly as possible for 12 seconds; this test can be used to check the internal consistency of other tests and the extent of co-operation by the patient, important when assessing possible neuromuscular weakness affecting respiration. There are several other more sophisticated tests which may not be necessary when assessing most patients. Measurement of arterial blood gases is also an important part of any assessment of lung function.... pulmonary function tests
The symptoms depend upon the site of the infection. General symptoms such as fever, weight loss and night sweats are common. In the most common form of pulmonary tuberculosis, cough and blood-stained sputum (haemoptysis) are common symptoms.
The route of infection is most often by inhalation, although it can be by ingestion of products such as infected milk. The results of contact depend upon the extent of the exposure and the susceptibility of the individual. Around 30 per cent of those closely exposed to the organism will be infected, but most will contain the infection with no signi?cant clinical illness and only a minority will go on to develop clinical disease. Around 5 per cent of those infected will develop post-primary disease over the next two or three years. The rest are at risk of reactivation of the disease later, particularly if their resistance is reduced by associated disease, poor nutrition or immunosuppression. In developed countries around 5 per cent of those infected will reactivate their healed tuberculosis into a clinical problem.
Immunosuppressed patients such as those infected with HIV are at much greater risk of developing clinical tuberculosis on primary contact or from reactivation. This is a particular problem in many developing countries, where there is a high incidence of both HIV and tuberculosis.
Diagnosis This depends upon identi?cation of mycobacteria on direct staining of sputum or other secretions or tissue, and upon culture of the organism. Culture takes 4–6 weeks but is necessary for di?erentiation from other non-tuberculous mycobacteria and for drug-sensitivity testing. Newer techniques involving DNA ampli?cation by polymerase chain reaction (PCR) can detect small numbers of organisms and help with earlier diagnosis.
Treatment This can be preventative or curative. Important elements of prevention are adequate nutrition and social conditions, BCG vaccination (see IMMUNISATION), an adequate public-health programme for contact tracing, and chemoprophylaxis. Radiological screening with mass miniature radiography is no longer used.
Vaccination with an attenuated organism (BCG – Bacillus Calmette Guerin) is used in the United Kingdom and some other countries at 12–13 years, or earlier in high-risk groups. Some studies show 80 per cent protection against tuberculosis for ten years after vaccination.
Cases of open tuberculosis need to be identi?ed; their close contacts should be reviewed for evidence of disease. Adequate antibiotic chemotherapy removes the infective risk after around two weeks of treatment. Chemoprophylaxis – the use of antituberculous therapy in those without clinical disease – may be used in contacts who develop a strong reaction on tuberculin skin testing or those at high risk because of associated disease.
The major principles of antibiotic chemotherapy for tuberculosis are that a combination of drugs needs to be used, and that treatment needs to be continued for a prolonged period – usually six months. Use of single agents or interrupted courses leads to the development of drug resistance. Serious outbreaks of multiply resistant Mycobacterium tuberculosis have been seen mainly in AIDS units, where patients have greater susceptibility to the disease, but also in developing countries where maintenance of appropriate antibacterial therapy for six months or more can be di?cult.
Streptomycin was the ?rst useful agent identi?ed in 1944. The four drugs used most often now are RIFAMPICIN, ISONIAZID, PYRAZINAMIDE and ETHAMBUTOL. Three to four agents are used for the ?rst two months; then, when sensitivities are known and clinical response observed, two drugs, most often rifampicin and isoniazid, are continued for the rest of the course. Treatment is taken daily, although thrice-weekly, directly observed therapy is used when there is doubt about the patient’s compliance. All the antituberculous agents have a range of adverse effects that need to be monitored during treatment. Provided that the treatment is prescribed and taken appropriately, response to treatment is very good with cure of disease and very low relapse rates.... nature of the disease tuberculosis has
Chronic bronchitis is typi?ed by chronic productive cough for at least three months in two successive years (provided other causes such as TUBERCULOSIS, lung cancer and chronic heart failure have been excluded). The characteristics of emphysema are abnormal and permanent enlargement of the airspaces (alveoli) at the furthermost parts of the lung tissue. Rupture of alveoli occurs, resulting in the creation of air spaces with a gradual breakdown in the lung’s ability to oxygenate the blood and remove carbon dioxide from it (see LUNGS). Asthma results in in?ammation of the airways with the lining of the BRONCHIOLES becoming hypersensitive, causing them to constrict. The obstruction may spontaneously improve or do so in response to bronchodilator drugs. If an asthmatic patient’s airway-obstruction is characterised by incomplete reversibility, he or she is deemed to have a form of COPD called asthmatic bronchitis; sufferers from this disorder cannot always be readily distinguished from those people who have chronic bronchitis and/ or emphysema. Symptoms and signs of emphysema, chronic bronchitis and asthmatic bronchitis overlap, making it di?cult sometimes to make a precise diagnosis. Patients with completely reversible air?ow obstruction without the features of chronic bronchitis or emphysema, however, are considered to be suffering from asthma but not from COPD.
The incidence of COPD has been increasing, as has the death rate. In the UK around 30,000 people with COPD die annually and the disorder makes up 10 per cent of all admissions to hospital medical wards, making it a serious cause of illness and disability. The prevalence, incidence and mortality rates increase with age, and more men than women have the disorder, which is also more common in those who are socially disadvantaged.
Causes The most important cause of COPD is cigarette smoking, though only 15 per cent of smokers are likely to develop clinically signi?cant symptoms of the disorder. Smoking is believed to cause persistent airway in?ammation and upset the normal metabolic activity in the lung. Exposure to chemical impurities and dust in the atmosphere may also cause COPD.
Signs and symptoms Most patients develop in?ammation of the airways, excessive growth of mucus-secreting glands in the airways, and changes to other cells in the airways. The result is that mucus is transported less e?ectively along the airways to eventual evacuation as sputum. Small airways become obstructed and the alveoli lose their elasticity. COPD usually starts with repeated attacks of productive cough, commonly following winter colds; these attacks progressively worsen and eventually the patient develops a permanent cough. Recurrent respiratory infections, breathlessness on exertion, wheezing and tightness of the chest follow. Bloodstained and/or infected sputum are also indicative of established disease. Among the symptoms and signs of patients with advanced obstruction of air?ow in the lungs are:
RHONCHI (abnormal musical sounds heard through a STETHOSCOPE when the patient breathes out).
marked indrawing of the muscles between the ribs and development of a barrel-shaped chest.
loss of weight.
CYANOSIS in which the skin develops a blue tinge because of reduced oxygenation of blood in the blood vessels in the skin.
bounding pulse with changes in heart rhythm.
OEDEMA of the legs and arms.
decreasing mobility.
Some patients with COPD have increased ventilation of the alveoli in their lungs, but the levels of oxygen and carbon dioxide are normal so their skin colour is normal. They are, however, breathless so are dubbed ‘pink pu?ers’. Other patients have reduced alveolar ventilation which lowers their oxygen levels causing cyanosis; they also develop COR PULMONALE, a form of heart failure, and become oedematous, so are called ‘blue bloaters’.
Investigations include various tests of lung function, including the patient’s response to bronchodilator drugs. Exercise tests may help, but radiological assessment is not usually of great diagnostic value in the early stages of the disorder.
Treatment depends on how far COPD has progressed. Smoking must be stopped – also an essential preventive step in healthy individuals. Early stages are treated with bronchodilator drugs to relieve breathing symptoms. The next stage is to introduce steroids (given by inhalation). If symptoms worsen, physiotherapy – breathing exercises and postural drainage – is valuable and annual vaccination against INFLUENZA is strongly advised. If the patient develops breathlessness on mild exertion, has cyanosis, wheezing and permanent cough and tends to HYPERVENTILATION, then oxygen therapy should be considered. Antibiotic treatment is necessary if overt infection of the lungs develops.
Complications Sometimes rupture of the pulmonary bullae (thin-walled airspaces produced by the breakdown of the walls of the alveoli) may cause PNEUMOTHORAX and also exert pressure on functioning lung tissue. Respiratory failure and failure of the right side of the heart (which controls blood supply to the lungs), known as cor pulmonale, are late complications in patients whose primary problem is emphysema.
Prognosis This is related to age and to the extent of the patient’s response to bronchodilator drugs. Patients with COPD who develop raised pressure in the heart/lung circulation and subsequent heart failure (cor pulmonale) have a bad prognosis.... chronic obstructive pulmonary disease (copd)
By the blood and lymph cancer may be transferred (metastasised) to the lymph nodes under the arm, liver, brain or lungs. An association has been shown between a low intake of Vitamin A and lung cancer. Causes: occupational hazards, environmental pollution, radiation, keeping of pet birds. Cigarette smoking is a strong risk factor. Studies show that a high Vitamin A/carotene intake is protective against the disease in men. Among women, evidence of a similar protective effect has not been found. Vitamin C reduces cancer risk. The increased prevalence of smoking among women results in more female lung cancer. All smokers should drink freely carrot juice (Vitamin A).
Symptoms. Chronic irritative cough, difficult breathing, pain in the chest, recurrent spitting of blood, clubbing of fingers, weight loss.
Alternatives. Only transient benefit is obtainable, yet it may be sufficient to achieve a measure of relief from distressing symptoms. See: CANCER: GENERAL REMARKS. Mullein tea has its supporters. Bugleweed strengthens lung tissue and supports the action of the heart. Blood root is known to arrest bleeding (haemoptysis).
Tea. Equal parts: Red Clover, Gota Kola, Mullein. 2 teaspoons to each cup boiling water; infuse 5-15 minutes. 1 cup three or more times daily.
Formula No 1. Equal parts: Elecampane, Violet, Red Clover, Echinacea. Mix. Dose: Powders: 750mg (three 00 capsules or half a teaspoon). Liquid extracts: 1-2 teaspoons. Tinctures: 1-3 teaspoons. Thrice daily and, if necessary, at bedtime for relief.
Formula No 2. Tincture Blood root 10 drops; Liquid extract Dogwood 20 drops; Liquid extract Elecampane 200 drops (14ml); Liquid extract Bugleweed (Lycopus europ) 30 drops. Flavour with Liquorice if necessary. Dose: 1-2 teaspoons in water 3 or more times daily. (W. Burns-Lingard MNIMH)
Where accompanied by active inflammation, anti-inflammatories are indicated: Mistletoe, Wild Yam, etc.
Diet. A substance in fish oil has been shown to experimentally prevent cancer of the lung. Mackerel, herring and sardines are among fish with the ingredient. See: DIET – CANCER.
Chinese Herbalism. See: CANCER – CHINESE PRESCRIPTION.
Treatment by a general medical practitioner or hospital oncologist. ... cancer – pulmonary
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