It should be noted that the patient has type 2 diabetes, hypertriglyceridemia, renal lithiasis and tachycardia (unspecified). He regularly takes medications for these conditions (metformin, saxagliptin, metoprolol, atorvastatin) and has started taking naproxen and omeprazole for abdominal symptoms. No recent travel, no contact with sick people, no new foods.
On clinical examination, it presents the following characteristics:
- Vital values: temperature 36.8°C, oxygen saturation 99%, respiratory rate 16 breaths per minute (rpm), heart rate 134 beats per minute (bpm), blood pressure 95/52 mmHg.
- Skin and appendages: perioral edema, papules on the scalp, neck, shoulders, abdomen and groin.
- Abdomen diffusely soft and tender to palpation, without signs of peritoneal irritation, hepatomegaly, or splenomegaly.
- Absence of pathological adenopathies.
Clinical reasoning and differential diagnosis
All of the patient’s symptoms are relatively nonspecific and could be due to multiple causes. For example, presyncope may be the consequence of intravascular depletion secondary to gastrointestinal symptoms, themselves of infectious or autoimmune origin (as in the case of celiac disease).
A potential unifying hypothesis lies in the activation of mast cells, which play a role in allergic reactions. This activation can be triggered by environmental exposures, foods, medications, or underlying conditions associated with an increase in mast cells, such as mastocytosis or mast cell activation syndrome. The release of histamine and other mediators can lead to symptoms affecting multiple organs, as is the case here. Adding the examination and vital signs to the equation, one must consider the possibility of anaphylactic shock.
Another possibility, although unlikely, is angioedema, either hereditary or drug-induced.
To refine the differential diagnosis, it is necessary to resort to additional examinations.
Additional tests
The first ones available urgently are the following:
- Electrocardiogram: sinus tachycardia with inverted T wave in lead III and aVF.
- Analyses : 26 500 leucocytes/mm3 (with neutrophilia), normal hemoglobin, creatinine 1.8 mg/dl, lactate 3.3 mmol/l (normal range 0.5-1.6). Elevated troponin, elevated procalcitonin.
The presence of neutrophilia may be a sign of infection as well as anaphylaxis. On the other hand, the lactate level indicates inadequate tissue perfusion and the troponin suggests that blood flow to the heart may be insufficient (not coronary but hemodynamic ischemia), which is consistent with the electrocardiogram findings. The elevated procalcitonin level is rather consistent with an infectious cause.
Evolution and updating of differential diagnosis
The patient presents with clinical worsening, his blood pressure dropping to 75/10 mmHg. Intensive serotherapy is implemented, up to a total of 4 liters of 0.9% physiological serum, and allows the patient to be stabilized at 114/65 mmHg.
After summarizing the information, we are dealing with a possible shock, which could be either anaphylaxis or sepsis. Adrenaline is prescribed urgently and broad-spectrum empirical antibiotic therapy is put in place.
After stabilization, a CT scan of the abdomen and pelvis was performed, which showed colonic diverticulosis and left renal lithiasis as the only findings, without signs of complications.
The patient presents with a new episode of hypotension manifested by a heart rate of 130 bpm and a blood pressure of 95/52 mmHg, which improve after administration of 2 liters of saline, reducing the heart rate to 110 bpm and blood pressure at 120/80 mmHg. At this point, he is admitted to the intensive care unit (ICU) and receives the following treatment:
Over the next few hours, the patient receives 10 liters of saline, his blood pressure remains normal, and the results of the follow-up blood test show improvement in kidney function as well as troponin, procalcitonin, and lactate levels.
The next day, the abdominal pain and rash subsided, as did the leukocytosis. Blood and urine cultures were sterile, so antibiotic therapy was discontinued.
After 72 hours, the patient begins to experience chest pain and dyspnea, the rash worsens again, tachycardia and hypotension reappear. On examination, he has desaturated and has bilateral expiratory wheezing.
Adrenaline is administered, which relieves symptoms almost immediately. The treatment given for anaphylaxis is repeated with good results.
Initial workup results are received and show elevated serum immunoglobulin E (IgE) and tryptase levels. The serum C4 level is 70 mg/dl (normal range 15-56), which excludes hereditary angioedema.
After presenting the clinical case, we invite you to propose the most likely diagnosis. (Knowing, however, that there may still be an essential element missing from the picture, which the patient will only reveal after being questioned in a targeted manner, as was the case here.) In a second part of this case study on “health and climate change”, we will solve the case and see why it is linked to this theme.
This case study was originally published on Univadis.es.
