A 58-year-old man with no significant medical history presents to the Emergency Department for acute abdominal pain. He is given a diagnosis of acute gastroenteritis and is discharged. Before he leaves, he is told to follow up with his primary care provider because of a small right lung opacity discovered on his chest x-ray. The opacity is 2 cm and completely surrounded by lung parenchyma. The patient is upset because he eats healthy, exercises regularly, has never smoked, and gets an annual physical examination. He denies any fatigue, night sweats, weight loss, cough, or dyspnea, and he reports no previous chest imaging.
Which of the following should be done next in the diagnostic workup?
CT scan. This patient is presenting with an incidentally discovered solitary pulmonary nodule (SPN). (E) Most of these nodules are benign (granulomas or hamartomas); however, there is still a significant risk that it is cancerous and thus observation alone is not appropriate. The first step with an SPN is to obtain previous chest imaging to see if it was present before or has grown, and to take a good history looking for lung cancer risk factors (smoking, family history of cancer, etc.). CT of the chest should be performed afterward to better characterize the nodule. The risk of cancer increases based on the size and shape of the nodule, with a spiculated pattern being worrisome. Once all of this information is collected, and the patient is at low risk, he can be followed with serial CT scans for 2 years; if there is no growth over this time, the serial CTs can be discontinued. (B) If the risk is intermediate, then a biopsy should be performed. (C) If the risk is high, then the nodule should be surgically removed. (D) The vignette does not mention when he had his last colonoscopy, but he sees his physician annually and likely received one at the age of 50 and therefore will receive another one at the age of 60. There is no suggestion of metastatic colon cancer in the vignette.
A 58-year-old woman presents to the hospital with shortness of breath. There is dullness to percussion at her lung bases, and a thoracentesis is performed. The following results are obtained.
Based on these findings, which of the following is the most likely underlying diagnosis?
Nephrotic syndrome. Any new onset pleural effusion should be “tapped” (thoracentesis) for diagnostic purposes. The first step in determining the etiology is to differentiate between a transudative process and an exudative process. An exudate is diagnosed when one or more of Light’s criteria are met: the ratio of total pleural fluid protein to total serum protein is >0.5, the ratio of total pleural fluid LDH to total serum LDH is >0.6, or the total pleural fluid LDH is greater than two-thirds the upper limit of normal of serum LDH. Light’s criteria is very sensitive but not as specific, so it can misdiagnose a transudate as an exudate (further studies can be performed, which are typically beyond the scope of the shelf examination).
Transudates are usually caused by systemic processes resulting in a disruption of hydrostatic or oncotic pressures. Common causes include congestive heart failure, cirrhosis, and nephrotic syndrome. (B, C, D) Exudates typically imply local processes and are a result of inflammation causing capillary leak or abnormalities in lymphatic drainage. Rheumatoid arthritis, tuberculosis, and malignancy are all examples of exudative processes. Other examples include any pulmonary infection, pulmonary embolism, systemic lupus erythematosus and other collagen vascular diseases, pancreatitis, hemothorax, and chylothorax. The above is just a partial list, and differentiating the cause of an exudate is much more difficult than a transudate. A useful flowchart for the diagnosis and management of pleural effusions is shown in Figure below.
A 68-year-old woman presents to the Emergency Department with shortness of breath and right upper quadrant pain. She has a long history of hypertension and COPD, for which she takes captopril and a variety of inhaled medications including ipratropium, albuterol, salmeterol, and fluticasone. Her vitals show a temperature of 37°C, blood pressure of 102/64 mmHg, heart rate of 108 beats per minute, respiratory rate of 30 breaths per minute, and oxygen saturation of 83% on room air. When speaking, she is gasping for air in between words and using accessory muscles of respiration. Her jugular veins are distended, and she has a right ventricular heave with an S4 and a holosystolic murmur at the left lower sternal border. Breath sounds are decreased bilaterally, with scattered wheezes and rhonchi heard over the lung fields without significant rales. In addition, there is hepatomegaly and pitting edema around the ankles. An ECG shows right axis deviation with a right bundle branch block.
Which of the following could have delayed the onset of this complication?
Home oxygen therapy. Cor pulmonale is defined as right ventricular dysfunction as a result of lung disease. COPD is the most common cause of cor pulmonale and causes pulmonary hypertension from emphysematous destruction of the lung parenchyma and vasculature. Chronic pulmonary hypertension will eventually cause right heart failure, which will manifest with jugular venous distention, hepatomegaly, and edema. Important signs of right heart strain from pulmonary hypertension include tricuspid regurgitation, right ventricular heave, S4, and ECG findings of right ventricular hypertrophy. Home oxygen therapy delays the onset of this deadly complication of COPD by decreasing hypoxemic pulmonary vasoconstriction and therefore decreasing the pressure in the pulmonary artery. This is an important treatment for advanced COPD and has been shown to improve mortality. (A) Digoxin is a cardiac glycoside that increases contractility of the ventricles. It is used for symptomatic relief in heart failure; however, it is not very useful in isolated right heart failure and would not delay the development of cor pulmonale in this patient. (B) Diuresis is an option for treating heart failure; however, it would not delay the development of cor pulmonale. Diuresis is complicated in patients with cor pulmonale. Some reduction in excessive preload will improve right ventricular cardiac output, but they are also very preload dependent and their cardiac output will decrease quickly if they are diuresed too much. (C) Vaccination is an important preventive measure in patients with COPD to reduce the risk of serious lung infections that cause life-threatening acute exacerbations. This patient is afebrile and having shortness of breath as a result of right heart failure, not a respiratory infection.
A 28-year-old woman with a history of asthma presents to the Emergency Department complaining of an “asthma attack.” She regularly uses inhaled albuterol and fluticasone, but is experiencing worsening shortness of breath for the past hour and is not responding to the albuterol inhaler. She broke her tibia in a skiing accident 1 week ago and an open reduction with internal fixation was performed. She takes oral contraceptive pills but denies using any other medications. On examination, her heart rate is 115 beats per minute, her respiratory rate is 28 breaths per minute, and her oxygen saturation is 94%. There are no murmurs or abnormal lung sounds. There is a cast on her right lower leg, and the right thigh above the cast is swollen and erythematous compared to the left thigh.
Which of the following is the most likely diagnosis?
Pulmonary embolism. Despite the fact that the patient has asthma and claims to be having an exacerbation, there is no significant wheezing on examination, suggesting an alternative diagnosis. The patient has several risk factors for pulmonary embolism, meeting the three categories of Virchow triad of thrombosis: stasis (likely has some degree of inactivity from her fractured tibia), endothelial injury (fractured tibia and orthopedic surgery), and a hypercoagulable state (oral contraceptive pills). Though the modified Wells criteria does not need to be memorized for the examination, it is useful for the discussion of pretest probabilities concerning the diagnosis of pulmonary embolism. The patient has at least a score of 6 points (3 points for clinical signs of a DVT in the injured leg, 1.5 points for tachycardia, and 1.5 points for recent surgery), although an argument could be made for adding 3 additional points since pulmonary embolism is the most likely diagnosis compared to alternative diagnoses. This gives her a high probability of having a pulmonary embolism (high probability is >6 points, intermediate is 2–6 points, and low is <2 points). Other potential points in the modified Wells criteria include the presence of hemoptysis or malignancy (1 point each) and a history of prior DVTs or pulmonary emboli (1.5 points). A CT angiogram would be the appropriate next step in diagnosis, and she should receive empiric anticoagulation.
(B) Fat embolism can occur as a result of a long bone fracture; however, this usually occurs within days of the trauma. Fat emboli syndrome is a distinct entity and presents with dyspnea, neurologic findings, and a petechial rash. (C) As mentioned previously, this patient has a history of asthma but you should avoid the temptation to explain her current symptoms with that diagnosis. Always recognize other important historical and physical findings that might fit another diagnosis better. (D) Viral bronchitis (like an asthma exacerbation) would present with marked wheezing, which is not seen in this patient.
A 24-year-old man presents with a 1-day history of shortness of breath and hemoptysis. He denies any fever or malaise, and has no significant past medical history. He does not take any medications, smoke, or use illicit drugs; he has not traveled recently or been exposed to any sick contacts. His laboratory values are shown below.
Urinalysis shows 1+ protein with red blood cells and red blood cell casts. There are pulmonary infiltrates on chest x-ray, and a renal biopsy shows linear deposits of IgG along the glomerular capillaries on immunofluorescence.
What other disease process has a similar pathophysiologic mechanism to this patient’s disease?
Pemphigus vulgaris. For patients presenting with pulmonary hemorrhage and renal failure, always consider Goodpasture syndrome and Wegener granulomatosis (now called granulomatosis with polyangiitis). Although lupus and Henoch–Schönlein purpura can cause these findings, it is rare for these diseases to manifest this way and they are less commonly tested. One other important diagnosis to consider is infective endocarditis, since embolic phenomena can affect the lungs and the kidneys; however, for this to happen, both right-sided and left-sided heart valves would have to be infected.
This patient has Goodpasture syndrome, which is suggested by the findings of pulmonary infiltrates on chest x-ray with hemoptysis (pulmonary alveolar hemorrhage) and nephritic syndrome. The diagnosis is confirmed with serum anti-glomerular basement membrane antibodies (anti-GBM) or renal biopsy showing a linear pattern of IgG deposition along the glomerular capillaries. Treatment is with plasma exchange and immunosuppressive medication (prednisone or cyclophosphamide).
The pathophysiology of Goodpasture involves a type II hypersensitivity reaction in which serum antibodies bind to self-antigens (α-3 chain of type IV collagen, which is found in basement membranes) causing cell death and tissue damage. Pemphigus vulgaris is another type II hypersensitivity reaction in which autoantibodies are directed at desmoglein 1 and/or 3, causing disruption of cell-to-cell adhesion and resulting in skin vesicles, bullae, and erosions. (B) Shellfish allergy is a type I hypersensitivity reaction in which previous sensitization to a shellfish antigen causes development of IgE, which links to mast cells and causes massive histamine release and anaphylaxis upon re-exposure to the antigen. (C) The tuberculin skin test operates via a delayed type IV hypersensitivity reaction, which involves memory T-cells that respond to the antigen and activate macrophages. This process takes approximately 48 hours to occur. (D) Lupus nephritis is a type III hypersensitivity reaction involving immune complex formation, which deposit in tissues and activate the complement cascade and the acute inflammatory response. Because the immune complexes deposit heterogeneously along glomerular capillaries, they will not cause a linear pattern as is seen in Goodpasture’s. Remember that type IV hypersensitivity reactions involve T-cells, whereas the other three involve antibodies (IgE in type I and primarily IgG in types II and III).