Respiratory Problems in the Tropics
Most clinicians in the tropics can achieve a great deal through careful history-taking and physical examination, judicious choice of which tests to do and which not to do, and a thorough knowledge of which diseases are important in the patient’s environment.
Many patients are suffering from conditions such as chronic obstructive airways disease (COAD)
e.g. pulmonary schistosomiasis (patterns differ greatly from one region to another)
The acquired immune deficiency syndrome (AIDS) epidemic has had a major impact on the pattern of respiratory disease in the tropics, particularly in its effects on the incidence and manifestations of tuberculosis.
The possibility of underlying human immunodeficiency virus (HIV) infection must influence the interpretation of symptoms and signs in patients with pulmonary problems.
Look for previous events or current symptoms that might suggest HIV-related disease.
A patient who works with animals or birds may be exposed to zoonotic diseases that sometimes have a pulmonary component: tularaemia, Q-fever, leptospirosis or psittacosis.
Mitral stenosis is much more common in developing countries.
In areas where gnathostomiasis occurs, enquire about eating habits; where schistosomiasis is prevalent consider the life style and likelihood of contact with schistosomal water.
Pneumonic plague in contracted by inhalation from a close contact dying of septicaemic plague.
Look for features suggestive of immunosupression: current or recent herpes zoster, oral candidiasis and wasting.
Look carefully for evidence of cardiac or abdominal abnormalities.
It is easy to miss pericardial constriction or effusion, which may complicate pulmonary disease.
Right ventricular hypertrophy may develop in chronic pulmonary disease; it is sometimes a feature of pulmonary schistosomiasis.
The following tests can contribute to diagnosis:
• HIV serology test
• Microscopy of the stained sputum smear
• Bacterial culture is of limited value
• In HIV-infected patients, pulmonary tuberculosis is more likely to be sputum-negative than in other people.
Improved samples can be obtained by physiotherapy or by initiating a deep cough by spraying the vocal cords with a fine saline spray or by injecting 1 ml of sterile saline direct into the trachea through a fine needle inserted between the thyroid and cricoid’s cartilages.
• Chest radiographs are important (susceptible to misinterpretation)
• Fibroeptic bronchoscopy may provide information towards diagnosis. (must be cleaned adequately after each investigation, to eliminate the risk of HIV transmission).
Acute Lobar Pneumonia
It is a major cause of death in the tropics, especially in children.
Bacterial pneumonias are often preceded by a viral infection that presumably alters the susceptibility of the host or damages local defense mechanisms.
Note also the immune status of the host:
• The HIV-infected individual
• The autosplenectomized sickler
• The postsplenectomy patient
• The pregnant woman
• The alcoholic
• The diabetic
• The malnourished
All have an increased susceptibility to bacterial infections
The symptoms and signs of lobar pneumonia may be confusing.
• Presence of fever
• Shallow tachypnoea
• Jaundice is possible
• Reduced chest movement
• The absence of any auscultatory signs
Pneumococci and Haemophilus influenzae have been the most common bacterial agents identified in most studies of lobar pneumonia.
The organism may be identified by blood culture in about one-third of patients, or by detecting bacterial antigen in blood or urine.
In legionella pneumonia there may be mental confusion, diarrhoea or hypotension; hyponatraemia and haematuria are common.
Tetracycline is the drug of choice but erythromycin is also effective.
A severely ill patient may have staphylococcal pneumonia, in which multiple lung cavities may develop.
Many such patients are assumed to have sputum-negative tuberculosis and are given antituberculous drugs.
Chloramphenicol is usually as effective and a lot less expensive.
The post primary tuberculosis may present with a clinical syndrome indistinguishable from acute bacterial pneumonia.
• Melioidosis should be considered as a possible cause of both acute and of unresolving pneumonia in the debilitated or immunocompromised.
• Viral pneumonia cannot reliably be distinguished clinically from bacterial: the latter may complicate upper respiratory tract viral infections.
• Radiographs usually show scattered reticulonodular shadows in both lungs.
• Diagnosis is most reliably made by transbronchial biopsy through a fibreoptic bronchoscope
• Co-trimoxazole is the treatment of choice
• Pentamidine may be tried if co-trimoxazole fails.
• In south Africa, pneumococci resistant to penicillin have become common enough to alter treatment policy.
• Possible complications: lung abscess, empyema, or metastatic (cerebral) abscess.
Pleural Effusion
Quite common in young adults with post primary tuberculosis.
• A history of pleuritic pain;
• Breathlessness;
• Stony dullness or percussion;
• Abnormal lymph nodes;
• High protein content.
Management:
The copper sulphate solution (2.37g. of dried crystals dissolved in water to a volume of 100 ml.)
Effusion containing 3.0-3.5 g/dl of protein
Take a pleural biopsy (Abram’s needle)
Bronchial Asthma
There are some differences in the pattern of disease from that seen in temperate countries:
• A history of rhinitis
• No eozema
• Positive skin tests to one or more allergens
Treatment:
• ß2-agonists(salbutamol or terbutaline)
• Cromoglycate may be assessed for prophylactics
• Short courses of oral corticosteroids (prednisolone 60 mg daily for 3-5 days) with nebulized ß2-agonists by inhalation
• Antimalarial and antituberculous prophylaxis may be warranted.
In some areas patients with cough or wheeze may have tropical pulmonary eosinophilia
(Lung shadows on radiography are associated with a positive filarial serological fixation test)
Antifilarial treatment
Eosinophilia may occur due to migrating larval stages of Ascaris, hookworm or strongyloides infection.
HIV and the Lungs
Pulmonary symptoms are common in AIDS, and in many patients they are the first clinical manifestations of the disease.
Organisms causing opportunist infections include: mycobacterial, bacterial, fungal and viral agents.
Mycobacterium tuberculosis is the most common in tropical settings: the incidence of clinical tuberculosis is greatly increased in the presence of HIV infection.
TB in HIV-infected patients is more commonly diffuse, miliary or basal in its distribution than it is in patients without HIV infection.
• Drug reactions in patients without HIV-related disease.
• Extra pulmonary tuberculosis is more common in patients with HIV infection than in others.
• P. carinii may complicate immunosuppression caused by HIV infection.
• Bacterial and fungal pneumonias may be complicated in patients with HIV infection.
• Kaposi’s sarcoma and lymphomas present with pulmonary symptoms
Sarcoidosis
• Often misdiagnosed as sputum-negative tuberculosis or other chronic infection
• The possibility of sarcoidosis should be considered in patients with unresolving lung disease, especially in case of iridocyclitis, lymphadenopathy, central nervous system complications or hypercalcaemia.
Pulmonary aspects of the common parasitic diseases
• Lung involvement may complicate those infections; may be the major mode of presentation;
• Paragonimiasis must be considered in patients with cough, haemoptysis (often mistaken for tuberculosis)
• Hydatid cysts may produce a variety of lung problems
• Helminth infections (hookworm, Ascaris, Strongyloides)
• A larval stage of the parasite migrates through the lungs (causes cough, fever, dyspnoea, wheeze or haemoptysis)
• In schistosomiasis eggs may be deposited in pulmonary capillaries and arterioles, eliciting a granulomatous reaction
• Severe P. falciparum malaria – pulmonary problems have been reported in 5-15% of cases:
Pulmonary oedema due to therapeutic fluid overload;
Bronchopneumonia complicating deep coma;
Septal oedema;
Endothelial cell swelling;
Acidosis with resultant tachypnoea is common in severe childhood malaria.
Acute Respiratory Infection in Children
Respiratory diseases, particularly bacterial pneumonia, tuberculosis, measles and pertussis are major causes of death throughout the world. Children are at particular risk (2-5 million die every year)
The other major killers in children in Africa: diarrhoeal disease, malaria and malnutrition.
Lower respiratory infections are the most lethal, particularly in the tropics, where the risk of death from pneumonia in children aged 1-4 years has been recorded as 50 times as great as in the USA.
Upper respiratory infections are usually viral, but the causative agent is rarely identified (may progress to viral pneumonia or may be complicated by bacterial pneumonia.)
Of the responsible viruses, measles, respiratory syncitial virus and the influenza and Para influenza viruses are numerically most important.
The most common bacteria:
• Streptococcus pneumoniae (especially in infants with measles or influenza)
• Haemophilus influenzae
• Half of all cases of bacterial pneumonia have clinical or serological evidence of preceding virus infection.
Measures:
• Vaccination in infancy against tuberculosis, measles, diphtheria, and pertussis.
• Special vigilance for children at risk of death from respiratory infection.
• Give antibiotic treatment
• Additional vaccines against respiratory syncitial virus, pneumococci and Haemophilus influenzae.
Vocabulary
To achieve [ə` t∫i:v] Досягати
Thorough [`θǎrə] Досконалий
Be exposed to [ǐks`pəυzd tυ] Піддаватися до
Zoonotic diseases [zu:`nəυtǐk dǐ`zi:zǐs] Хвороби складних організмів
Septicaemic plague [sǐptǐ`kæmǐk`plǎg] Чума загального зараження
Zoster [`zəυstə] Поясничий лишай
Constriction [kən`strǐk∫n] Звуження, зжимання
Effusion [ǐ`fјu:зn] Вилив
Immunocompromised [ǐmјυnəυ`komprəma ǐzd] Імуноослаблений
Percussion [pə:`ku:∫n] Зіткнення, вистукування,перкусія
Agonists [`ægənǐst] Агоністи
Nebulized [`nјu:bјυl a ǐzd] Розпилений
Wheeze [`wi:z] Свист
Larval stages [`lα:vəl`steǐdзǐs] Личинкові стадії
Diffuse [dǐ`fјu:z] Розсіяний ,туманний
Be deposited [bǐ dǐ`po:zǐtǐd] Бути вкладеним ,поміщеним
Pertussis [pə`tјυsǐs] Коклюш
Vigilance [`vǐdзǐləns] Безсоння
Psittacosis [sǐtə`kəυsǐs] Пситакоз
Thyroid [`θa ǐroǐd] Щитовидний хрящ
Cricoid cartilages [krǐ`koǐd`kα:tǐlǐdз] Перстнеподібний хрящ
Sickler [`sǐklə] Жнець(хрящ)
Auscultatory signs [o:skəl`teǐtərǐ`sa ǐnz] Ознаки вислуховування
Shadows [`∫ædəυz] Тіні, потемніння
Copper sulphate [`kopə səl`feǐt] Сульфат міді
Be assessed [bǐ ə`sest] Бути визначеним ,оціненим
Filarial [fǐ`lærǐəl] Філаріальний
Fungal agents [`fǎŋgl`eǐdзǐnts] Грибкові, хвороботворчі начала
Miliary [`mǐlǐərǐ] Той, що супроводжується висипом
Resultant [rǐ`zǎltənt] Витікаючий из чогось(перен.)
Syncitial virus [sǐn`sǐ∫ǐəl`va ǐrǐs] Синситіальний вірус
Mitral stenosis [`mǐtrəl stǐ`nəυsǐs] Мітральний стеносіс
Be warranted [bǐ`worəntǐd] Бути гарантованим
Questions:
1) What are the conditions many patients in the tropics suffer from?
2) How many features are suggestive of immunosupression?
3) How should we provide adequate investigations in case of respiratory problems in the tropics?
4) Should we take into consideration the immune status of the host in case of Acute Lobar Pneumonia?
5) How can we manage bacterial infections of pneumonia?
6) What are the differences in the pattern of bronchial asthma in the tropics? What can be prophylaxis?
7) How does the pulmonary disease pattern depend on HIV infection?
Most clinicians in the tropics can achieve a great deal through careful history-taking and physical examination, judicious choice of which tests to do and which not to do, and a thorough knowledge of which diseases are important in the patient’s environment.
Many patients are suffering from conditions such as chronic obstructive airways disease (COAD)
e.g. pulmonary schistosomiasis (patterns differ greatly from one region to another)
The acquired immune deficiency syndrome (AIDS) epidemic has had a major impact on the pattern of respiratory disease in the tropics, particularly in its effects on the incidence and manifestations of tuberculosis.
The possibility of underlying human immunodeficiency virus (HIV) infection must influence the interpretation of symptoms and signs in patients with pulmonary problems.
Look for previous events or current symptoms that might suggest HIV-related disease.
A patient who works with animals or birds may be exposed to zoonotic diseases that sometimes have a pulmonary component: tularaemia, Q-fever, leptospirosis or psittacosis.
Mitral stenosis is much more common in developing countries.
In areas where gnathostomiasis occurs, enquire about eating habits; where schistosomiasis is prevalent consider the life style and likelihood of contact with schistosomal water.
Pneumonic plague in contracted by inhalation from a close contact dying of septicaemic plague.
Look for features suggestive of immunosupression: current or recent herpes zoster, oral candidiasis and wasting.
Look carefully for evidence of cardiac or abdominal abnormalities.
It is easy to miss pericardial constriction or effusion, which may complicate pulmonary disease.
Right ventricular hypertrophy may develop in chronic pulmonary disease; it is sometimes a feature of pulmonary schistosomiasis.
The following tests can contribute to diagnosis:
• HIV serology test
• Microscopy of the stained sputum smear
• Bacterial culture is of limited value
• In HIV-infected patients, pulmonary tuberculosis is more likely to be sputum-negative than in other people.
Improved samples can be obtained by physiotherapy or by initiating a deep cough by spraying the vocal cords with a fine saline spray or by injecting 1 ml of sterile saline direct into the trachea through a fine needle inserted between the thyroid and cricoid’s cartilages.
• Chest radiographs are important (susceptible to misinterpretation)
• Fibroeptic bronchoscopy may provide information towards diagnosis. (must be cleaned adequately after each investigation, to eliminate the risk of HIV transmission).
Acute Lobar Pneumonia
It is a major cause of death in the tropics, especially in children.
Bacterial pneumonias are often preceded by a viral infection that presumably alters the susceptibility of the host or damages local defense mechanisms.
Note also the immune status of the host:
• The HIV-infected individual
• The autosplenectomized sickler
• The postsplenectomy patient
• The pregnant woman
• The alcoholic
• The diabetic
• The malnourished
All have an increased susceptibility to bacterial infections
The symptoms and signs of lobar pneumonia may be confusing.
• Presence of fever
• Shallow tachypnoea
• Jaundice is possible
• Reduced chest movement
• The absence of any auscultatory signs
Pneumococci and Haemophilus influenzae have been the most common bacterial agents identified in most studies of lobar pneumonia.
The organism may be identified by blood culture in about one-third of patients, or by detecting bacterial antigen in blood or urine.
In legionella pneumonia there may be mental confusion, diarrhoea or hypotension; hyponatraemia and haematuria are common.
Tetracycline is the drug of choice but erythromycin is also effective.
A severely ill patient may have staphylococcal pneumonia, in which multiple lung cavities may develop.
Many such patients are assumed to have sputum-negative tuberculosis and are given antituberculous drugs.
Chloramphenicol is usually as effective and a lot less expensive.
The post primary tuberculosis may present with a clinical syndrome indistinguishable from acute bacterial pneumonia.
• Melioidosis should be considered as a possible cause of both acute and of unresolving pneumonia in the debilitated or immunocompromised.
• Viral pneumonia cannot reliably be distinguished clinically from bacterial: the latter may complicate upper respiratory tract viral infections.
• Radiographs usually show scattered reticulonodular shadows in both lungs.
• Diagnosis is most reliably made by transbronchial biopsy through a fibreoptic bronchoscope
• Co-trimoxazole is the treatment of choice
• Pentamidine may be tried if co-trimoxazole fails.
• In south Africa, pneumococci resistant to penicillin have become common enough to alter treatment policy.
• Possible complications: lung abscess, empyema, or metastatic (cerebral) abscess.
Pleural Effusion
Quite common in young adults with post primary tuberculosis.
• A history of pleuritic pain;
• Breathlessness;
• Stony dullness or percussion;
• Abnormal lymph nodes;
• High protein content.
Management:
The copper sulphate solution (2.37g. of dried crystals dissolved in water to a volume of 100 ml.)
Effusion containing 3.0-3.5 g/dl of protein
Take a pleural biopsy (Abram’s needle)
Bronchial Asthma
There are some differences in the pattern of disease from that seen in temperate countries:
• A history of rhinitis
• No eozema
• Positive skin tests to one or more allergens
Treatment:
• ß2-agonists(salbutamol or terbutaline)
• Cromoglycate may be assessed for prophylactics
• Short courses of oral corticosteroids (prednisolone 60 mg daily for 3-5 days) with nebulized ß2-agonists by inhalation
• Antimalarial and antituberculous prophylaxis may be warranted.
In some areas patients with cough or wheeze may have tropical pulmonary eosinophilia
(Lung shadows on radiography are associated with a positive filarial serological fixation test)
Antifilarial treatment
Eosinophilia may occur due to migrating larval stages of Ascaris, hookworm or strongyloides infection.
HIV and the Lungs
Pulmonary symptoms are common in AIDS, and in many patients they are the first clinical manifestations of the disease.
Organisms causing opportunist infections include: mycobacterial, bacterial, fungal and viral agents.
Mycobacterium tuberculosis is the most common in tropical settings: the incidence of clinical tuberculosis is greatly increased in the presence of HIV infection.
TB in HIV-infected patients is more commonly diffuse, miliary or basal in its distribution than it is in patients without HIV infection.
• Drug reactions in patients without HIV-related disease.
• Extra pulmonary tuberculosis is more common in patients with HIV infection than in others.
• P. carinii may complicate immunosuppression caused by HIV infection.
• Bacterial and fungal pneumonias may be complicated in patients with HIV infection.
• Kaposi’s sarcoma and lymphomas present with pulmonary symptoms
Sarcoidosis
• Often misdiagnosed as sputum-negative tuberculosis or other chronic infection
• The possibility of sarcoidosis should be considered in patients with unresolving lung disease, especially in case of iridocyclitis, lymphadenopathy, central nervous system complications or hypercalcaemia.
Pulmonary aspects of the common parasitic diseases
• Lung involvement may complicate those infections; may be the major mode of presentation;
• Paragonimiasis must be considered in patients with cough, haemoptysis (often mistaken for tuberculosis)
• Hydatid cysts may produce a variety of lung problems
• Helminth infections (hookworm, Ascaris, Strongyloides)
• A larval stage of the parasite migrates through the lungs (causes cough, fever, dyspnoea, wheeze or haemoptysis)
• In schistosomiasis eggs may be deposited in pulmonary capillaries and arterioles, eliciting a granulomatous reaction
• Severe P. falciparum malaria – pulmonary problems have been reported in 5-15% of cases:
Pulmonary oedema due to therapeutic fluid overload;
Bronchopneumonia complicating deep coma;
Septal oedema;
Endothelial cell swelling;
Acidosis with resultant tachypnoea is common in severe childhood malaria.
Acute Respiratory Infection in Children
Respiratory diseases, particularly bacterial pneumonia, tuberculosis, measles and pertussis are major causes of death throughout the world. Children are at particular risk (2-5 million die every year)
The other major killers in children in Africa: diarrhoeal disease, malaria and malnutrition.
Lower respiratory infections are the most lethal, particularly in the tropics, where the risk of death from pneumonia in children aged 1-4 years has been recorded as 50 times as great as in the USA.
Upper respiratory infections are usually viral, but the causative agent is rarely identified (may progress to viral pneumonia or may be complicated by bacterial pneumonia.)
Of the responsible viruses, measles, respiratory syncitial virus and the influenza and Para influenza viruses are numerically most important.
The most common bacteria:
• Streptococcus pneumoniae (especially in infants with measles or influenza)
• Haemophilus influenzae
• Half of all cases of bacterial pneumonia have clinical or serological evidence of preceding virus infection.
Measures:
• Vaccination in infancy against tuberculosis, measles, diphtheria, and pertussis.
• Special vigilance for children at risk of death from respiratory infection.
• Give antibiotic treatment
• Additional vaccines against respiratory syncitial virus, pneumococci and Haemophilus influenzae.
Vocabulary
To achieve [ə` t∫i:v] Досягати
Thorough [`θǎrə] Досконалий
Be exposed to [ǐks`pəυzd tυ] Піддаватися до
Zoonotic diseases [zu:`nəυtǐk dǐ`zi:zǐs] Хвороби складних організмів
Septicaemic plague [sǐptǐ`kæmǐk`plǎg] Чума загального зараження
Zoster [`zəυstə] Поясничий лишай
Constriction [kən`strǐk∫n] Звуження, зжимання
Effusion [ǐ`fјu:зn] Вилив
Immunocompromised [ǐmјυnəυ`komprəma ǐzd] Імуноослаблений
Percussion [pə:`ku:∫n] Зіткнення, вистукування,перкусія
Agonists [`ægənǐst] Агоністи
Nebulized [`nјu:bјυl a ǐzd] Розпилений
Wheeze [`wi:z] Свист
Larval stages [`lα:vəl`steǐdзǐs] Личинкові стадії
Diffuse [dǐ`fјu:z] Розсіяний ,туманний
Be deposited [bǐ dǐ`po:zǐtǐd] Бути вкладеним ,поміщеним
Pertussis [pə`tјυsǐs] Коклюш
Vigilance [`vǐdзǐləns] Безсоння
Psittacosis [sǐtə`kəυsǐs] Пситакоз
Thyroid [`θa ǐroǐd] Щитовидний хрящ
Cricoid cartilages [krǐ`koǐd`kα:tǐlǐdз] Перстнеподібний хрящ
Sickler [`sǐklə] Жнець(хрящ)
Auscultatory signs [o:skəl`teǐtərǐ`sa ǐnz] Ознаки вислуховування
Shadows [`∫ædəυz] Тіні, потемніння
Copper sulphate [`kopə səl`feǐt] Сульфат міді
Be assessed [bǐ ə`sest] Бути визначеним ,оціненим
Filarial [fǐ`lærǐəl] Філаріальний
Fungal agents [`fǎŋgl`eǐdзǐnts] Грибкові, хвороботворчі начала
Miliary [`mǐlǐərǐ] Той, що супроводжується висипом
Resultant [rǐ`zǎltənt] Витікаючий из чогось(перен.)
Syncitial virus [sǐn`sǐ∫ǐəl`va ǐrǐs] Синситіальний вірус
Mitral stenosis [`mǐtrəl stǐ`nəυsǐs] Мітральний стеносіс
Be warranted [bǐ`worəntǐd] Бути гарантованим
Questions:
1) What are the conditions many patients in the tropics suffer from?
2) How many features are suggestive of immunosupression?
3) How should we provide adequate investigations in case of respiratory problems in the tropics?
4) Should we take into consideration the immune status of the host in case of Acute Lobar Pneumonia?
5) How can we manage bacterial infections of pneumonia?
6) What are the differences in the pattern of bronchial asthma in the tropics? What can be prophylaxis?
7) How does the pulmonary disease pattern depend on HIV infection?