Following text has been prepared from the answers given to the questions of panel members. Panel consisted of Dr Arshad Javaid Sh, Dr Mehboob Ashraf, Dr Liaqat Ali ch and Dr Saleem Akhtar Rana.Choice of questions belonged to the panel. Any error or mistake is the responsibility of the editorial board.
Division between Upper and lower respiratory tract infections.
· Infection occuring above vocal cards are upper RTIs and below these are LTRI.
· If on examination throat is congested and pus is present in the throat,then it is URTI.Otherwise cough is due to LRTI.Lot of expectoration is also symptom of LTRI
¨ These are benign and usually without complications.
¨ Infections are usually viral but soon get superadded infections. Common organisms are Streptococcus Pneumoniae, Haemophilus Influenzi, and Morixilla Catarhalis.
¨ Physicians should be at their toes. Delays of few hours in starting proper antibiotic can lead to spread of infections. Despite all advancements mortality rate is still 7-8 %. LRTIs can be followed by complications.
¨ Usaul pathogens are same as mentioned above as superadded infections. In addition to these Staph Aureus, Mycoplasma and Pseudomonas Aeroginosa should be always kept in mind.
Cough.
Cough has no diagnostic profile to offer. It is only detailed history about the onset of present illness and examination of throat and chest, which should lead to diagnosis.
q Pneumonias OR
q AECB i.e acute exacerbation of chronic bronchitis.
Distinction can be made while taking history. Duration of symptoms should decide. A Few days’ duration preceded by absolute normal period should mean Pneumonias.
Pneumonias can again be labelled as nosocomial (Acquired in Hospitals) or community acquired. Ceclor, Zinnat, Orelox and ciproxin are a good choice to treat L.R.T.I.
Important point to note.
While managing Pneumonias or AECBs one should be always looking for following signs of respiratory failure.
§ Cyanosis.
§ Extra effort by respiratory and extra respiratory muscles
§ Oedema
§ Cor pulmonale
These should mean respiratory failure. Patient should be immediately hospitalized. He is not expectorating properly and can drown in his own secretions.9-10 % patients can go into respiratory failure.
Suppression of Cough and use of Antihistamines.
Anithistamines are of absolutely no use in suppressing the cough. These cause sedation, dryness of mouth, nose, and throat. Secretions become thick. It can lead to consolidation or atelactasis. Congestion, dryness and sedation turn a simple illness into very uncomfortable condition. There are always complications such as sinusitis, eustachean tube blockage and atelactasis due to thick and viscous secretions.
Antihistamines can reduce cough only if it is purely allergic.
Cough suppressents should be used in proper full dosage to suppress dry and hackling cough. Hydrallin DM in this regard is a good combination. Bronchodialtors in low dose may relieve dry cough to some extent.
Interpretation of X-ray Chest.
Increased bronchovascular markings.
This term is non-specific. It does not convey anything. These changes may be of cardiac origin or respiratory origin. It should not mean anything to clinician.
Typical Tuberculous lesions.
Primary GOHN’s complex consists of small pathch in the periphery, connected by streaks to the hilum.
Thick walled, cavitating, ill-defined lesions with satellite lesions in the surroungings, connected with hilum by streaks are the characteristics of tuberculosis.
Malignant lesions are more circulars and more welldefined.
Management of atypical consolidations.
If there are lesions on the X-ray chest, which can not be definitely labelled, it is always better not to prescribe ATT right away. One should think many times before he starts ATT.He should exhuast all other possibilties. It is better to give a course of 2nd or 3rd generation cephalosporins or quinolones for 15 days and repeat Xray chest. Shadows should reduce by 50 % if it is non-tuberculous. If the size remains same or it has increased then ATT is in order provided malignancy is not a candidate for diagnosis.
He agreed with the panel that majority of the laboratory reports are negative for AFB.That becomes automatically a limiting factor for ordering further investigations. But he stressed that failure to detect AFB is not due its absence in the sputum but it is due to following two reasons.
Improper collection of specimen.
Most of the specimens going to laboratory are secretions of mouth or throat. Obviously these will be negative. Patient should be given a sterile tube. He should be asked to clear his mouth and throat from secretions by spitting outside. Then he should be asked to cough out sputum. When he is definite that sputum now is coming from deep down chest only then it should be collected in the tube and sent to the lab.
Faulty Lab techniques.
Second reason for false negative results is that technetians do not go for the thickest sputum present in the centre of specimen but rather they collect easily available periphereal secretions. If central thick part is examined properly then the yield must be very high.
Non contageous status of tuberculous patients.
When patient recieves proper ATT for 2-4 weeks, sputum becomes AFB negative. He becomes non-contageous. To be on the safe side it is better to use ATT for one month before declaring him non-contageous.
If recurrence occurs after complete healing then sputum again becomes AFB positive.
Tuberculosis in Upper respiratory tract.
Retropharyngeal abcess is well-documented tuberculous lesion. Tuberculous Otitis Media is another lesion, which has been documented. In our country where TB is so common these two conditions should be kept in mind.
If it does not respond withen 2 weeks use of proper antibiotics, It must be thoroughly investigated. Examination is essential.
Cough and Malignancy.
All suspect lesions should be subjected to bronchoscopic examination and biopsy. Following factors should always raise the possibility of malignancy in a patient of cough.
§ Increasing age
§ Smoking
§ Round shadow on radiograph.
§ Slowly progressing lesions.
§ Dry irritating cough.
§ Weight loss.
Brochography is now outdated as CT scan is available.
Cough Dyspnoea, and Wheezing.
To decide whether cough is of pulmonary origin or cardiac origin, character of cough is not much helpful. If dyspneoa is present then one should always think of CCF.ECG and echocardiography will make a final diagnosis.
If wheezing is associated with cough, one should note the area of distribution of wheezing. As in asthmatic conditions wheezing is more evenly distributed throughout the lungs. It should be of equal intensity in apical and basal regions. In CCF wheezing is more in basal regions than in apical regions.
Culture and sensitivity of sputum.
In all difficult cases proper specimen of sputum should be sent to laboratory for culture and sensitivity. It is more helpful in diagnosis than in spirometry. Isolation of offending organism and its sensitivity spectrum is quite useful in managing patients.
Vaccination for Asthma is losing favour worldwide. It is really not effective. Only in certain allergic conditions where allergin has been defined, it can give temporary relief.
Management of Steroid dependent Asthma.
It is always a problem to taper off steroid in-patients who are using these for years. In this regard calculation of daily requirement is necessary. If patient is using less than 10 mgs prednisolone per day (or Dexamethasone 2.5 mgs /day) then these can be immediately replaced by steroid inhalers. If patient is using more than this than reduce the dose slowly. In a schedule of Prednisolone 2.5 mgs /2 weeks or 0.5 mgs dexamethasone /2 weeks reductions.
DD of allergic and infective conditions in Upper respiratory tract.
Fever absent Present
Discharge copious Smallish
Watery Thick
Colourless Yellowish
General signs symptoms. Absent Present.
Erythromycin, Clarithromycin, Azithromycin.
While discussing antibiotics for different infections these three were also discussed. Most of the Erythromycin ingested is destroyed in stomach. Very low serum levels are achieved. While Clarithromycin and Azithromycin achieve good levels. Difference between these two is that Azithromycin is mostly availabe intracellur. While requirement is mostl for extracellurar levels. So Prof Zafa ullah Khan is in favour of Klarithromycin.