To the Editor: We thank Dr. Poddighi for his thoughtful commentary on our article regarding the clinical diagnosis of pertussis.1 We fully agree that the overall clinical impression, sometimes called “clinical gestalt,” is a vital diagnostic tool for many conditions. In fact, we are in the process of performing a systematic review of clinical gestalt for the diagnosis of a range of respiratory infections; we hope that study will shed more light on its accuracy.
Well-validated clinical decision rules (CDRs) can be very useful to support a physician's clinical gestalt. Of course, it is important to remember that CDRs are clinical decision support tools, not decision replacement tools. They must always be applied in the full context of what is known about a patient. For example, a Centor Score in the range of low or moderate probability will be interpreted differently if the clinician knows that a household member had been diagnosed with streptococcal pharyngitis the previous week. CDRs can also help physicians, especially those in training, learn what is important in a history and physical examination and what is not, even if they only integrate these signs and symptoms implicitly (ie, clinical gestalt) rather than explicitly using a CDR.
Finally, we fully agree with Dr. Poddighi's advice to always consider pertussis in the differential diagnosis of a patient with prolonged cough or typical signs and symptoms, such as the characteristic whoop, paroxysmal cough, or posttussive retching or vomiting. A previous systematic review by our research group showed that nearly 1 in 5 children with prolonged cough have pertussis.2
Notes
The above letter was referred to the author of the article in question, who offers the following reply.