A commentary on “Varicella pneumonia in an immunocompetent adult: A case report”

Abstract

Clinicians are typically quite familiar with chickenpox and with pneumonia, but not necessarily pneumonia due to varicella-zoster virus (VZV). In the US, prior to the varicella vaccine being released in 1995, chicken pox was nearly universal in children less than 15 years of age. This left few people to get chicken pox as an adult, and even less who actually got pneumonia; hence, many physicians are unfamiliar with varicella pneumonia. There were approximately 4 million cases yearly [1]. Mortality for chickenpox has always been low with only about 2 deaths per 100,000 cases. Because it is more severe in adults, the mortality rate is slightlyhigher at 15 deaths per 100,000 cases. A typical case involves a characteristic rash, fever and malaise. The “pox” are 5 mm raised, well-circumscribed, fleshcolored, erythematous vesicles that progress to ooze serous fluid, then become nodular, centrally umbilicated, and eventually crust over. They can coalesce to form patches. The various lesions spread centrifugally starting on the face and trunk, and are in different stages of progression, which distinguishes them from the uniform lesions of smallpox. There are several complications of chickenpox that can occur weeks or even decades later. Herpes zoster, or shingles, is the reactivation of VZV from a dorsal root ganglion or cranial nerve ganglion resulting in a painful, vesicular rash along the dermatome of the associated ganglion. Subsequently to that, cerebral angiitis can occur after reactivation of VZV from the trigeminal ganglion along the V 1 cranial nerve. Most complications, however, occur at the time of the initial chickenpox infection. Neurologic complications typically involve ataxia, which may be accompanied most notably by vomiting, vertigo, tremor, and dysarthria. When it occurs it is usually in children and is reversible. Encephalitis may also occur and is more serious with an altered sensorium, headaches, vomiting, fever and frequent seizures. Between 5 and 20% of those patients die, and up to 15% have neurologic sequelae. Varicella pneumonia is another serious complication in adults that can occur as a complication of chickenpox. Significant pneumonia typically occurs in immunosuppressed children or adults, but if it is in adults it accounts for a greater degree of morbidity and mortality. It only affects 2.3 of 400 cases of adult patients with chickenpox [2]. Once the rash starts, if pneumonia ensues, it is usually one to six days later. Symptoms include tachypnea, a nonproductive cough, dyspnea and fever. They may be worse in pregnant patients. The chest radiograph shows diffuse involvement of both lungs with interstitial pneumonitis, possibly with a nodular