Question

As an epidemiologist working for the World Health Organization for the past five years , Kelsey has lived in many parts of the world. For the past two years she served in the Emerging Disease Surveillance and Response Team stationed in Manila , Philippines About two months ago she traveled to the United States for a meeting . Over the past month , she has felt fatigued . She developed a cough that occasionally generates yellow -tinged sputum . She hadn't weighed herself in several weeks , but felt like her clothes were fitting more loosely . She was somewhat surprised , since she hadn't been trying to lose weight , but she had almost no appetite lately . She has not experienced a fever or chills . Kelsey went to a clinic in Manila , where she was prescribed a broad -spectrum antibiotic clarithromycin ) to treat what the doctor felt was probably a case of bronchitis .

After finishing the course of antibiotics , Kelsey feſt fatigued and her cough persisted . Within two days of finishing her course of clarithromycin she developed a fever , chills , night sweats , and she occasionally coughed up sputum that was tinged with blood (hemoptysis ) . After two days of these worsening symptoms she returned to the clinic where she meets you - the physician assistant on duty at the time .

After your routine exam, you discover that Kelsey has lost 10 pounds in the past 4-6 weeks . Questioning her further , you learn she is married and has been in good health until recently , she isn't diabetic , and is HIV negative . Kelsey is a nonsmoker who is up to date on her standard vaccines and booster shots . Her vaccine records show she had the bacillus Calmette Guérin vaccine as an infant . She did have a positive tuberculin skin test last year , but no signs of latent or active TB were found afterward .

You decide to order a chest X-ray , take a sample of her sputum for culture and microscopy analysis , and also order an interferon gamma release assay . You did not order a tuberculin skin test . While you wait for the test results , you admit Kelsey to the clinic and assign her to an isolation room .

1. As the PA on duty you have developed a working diagnosis to help you care for KelseyWhat disease do you suspect? What clues led you to your working diagnosis ?

3. If you working diagnosis is , what would those tests show? (That is, would her X-ray be normal or abnormal, and would her interferon gamma release assay be positive or negative?) What microscopy and culture of sputum findings might cause doubt about your initial diagnosis ?

5. Why is the patient's HIV status important in this case?

7. Why did the physician who first saw Kelsey assume she had bronchitis ?

Answer 1

1. Tuberculosis

An infectious disease caused by the bacterium , Mycobacterium Tuberculosis , mainly affecting the lungs , where it causes tubercles charecterised by the expectoration mucus and sputum , weight loss , chest pain and fever.

Clues : The main symptoms that indicated the presence of TB are present in her; such as coughing that continue for three weeks or more, fever , weight loss , chills , night sweats , coughing up blood etc. Also she had a Positive Tuberculin skin test last year.

2. If the patient is suffering with Tuberculosis, her

X- ray : X- ray of chest shows the cavitation of the lung tissues , caused by tbe bacterial infection.

Interferon - gamma release assay ( IGRA ) : is a bloodtest using antigens and controls. IGRA of a TB  patient shows positive result.

Microscopy and culture of sputum findigs :

Tuberculosis infection is   indicated by the Positive Acid fast staining technique during the Sputum smear microscopy , Detection of Myocobatcterium Tuberculosis during culture in Egg medium or broth.

Negative or Non Acid fast staining , negative sputum culture can give a doubt for present diagnosis.  

5. HIV status and its importance

* HIV infected individuals are more susceptible to develop Tuberculosis

* HIV infection in some people may cause negative test results for some other test, ( such as Tb ) as the immune system, which is responsible for test reactions , is not working properly

7. The first physician doubted the case as bronchitis due to the presence of Coughing and sputum production and she experienced the  fatigue for one month .