Case Presentation: A 23-year-old male with past medical history significant for recovered COVID 19 pneumonia one year prior presented to the Emergency Department with a chief complaint of shortness of breath with exertion that was gradually worsening. He endorsed increased weakness, fatigue, and pallor over a similar time span. The onset was two weeks prior. The patient had received the second dose of the Pfizer COVID vaccine one week prior to the onset of symptoms. Pertinent negatives were denial of any rashes, bruising, blood loss, weight loss, fevers, or chills. He also denied any sick contacts or new medications, and recent travel was unremarkable. Recent medical history was significant for severe COVID-19 pneumonia one year prior with a two-week hospitalization that required oxygen on discharge which he eventually was able to wean. He was unable to follow up with a primary care provider after his hospitalization. His labs were notable for a hemoglobin of 4.1 with a mean corpuscular volume of 89, a normal platelet count and white blood cell count, an erythrocyte sedimentation rate (ESR) of 120, C-reactive protein (CRP) of 6.1, a normal LDH, a total bilirubin of 1.4 with indirect being the primary component, and a high haptoglobin. Chest x-ray showed no consolidation or etiology of the shortness of breath and he maintained appropriate saturations room air. An ultrasound of the abdomen showed mild splenomegaly. An extensive workup began with a negative direct-coombs, reticulocyte count was low with concern for hypoproliferation. An iron panel was inconclusive. A comprehensive infectious panel (including Hepatitis C panel, Parvovirus, Epstein-barre virus, etc) was negative. Peripheral blood smear was significant for marked anemia and hypoproliferation. The patient underwent bone marrow biopsy which was significant for autoimmune myelofibrosis. JAK2 V617, Myeloproliferative leukemia, and CAL-R mutations were all negative. Systemic Lupus Erythematosus workup was also negative. He was referred to Rheumatology clinic for further workup which was unrevealing and the patient was diagnosed with AIMF secondary to COVID19 vs COVID19 vaccination.
Discussion: Myelofibrosis is a hematologic disorder defined by ineffective hematopoiesis due to bone marrow scarring. Primary myelofibrosis (PMF) is often seen in connection with myelodysplastic disorders, however, bone marrow fibrosis is also associated with a variety of non-malignant conditions called autoimmune myelofibrosis (AIMF). AIMF tends to have a more favorable clinical course than PMF. It is generally accepted that autoimmune responses in genetically predisposed individuals are often preceded by an environmental trigger. Of numerous potential precipitants, infections are generally the most common, usually by inducing an antigenic cross reaction. Many hematologic diseases have emerged since the onset of COVID-19 as problematic sequelae. The temporal relationship alone exhibited in this case is cause for consideration. Even more so, the addition of a negative autoimmune workup with an obvious antigenic immune-system insult is convincing of a COVID-19 vs. COVID vaccine induced AIMF, adding to the ever-growing list of potential hematologic complications of COVID-19.
Conclusions: To our knowledge, this is the first case of autoimmune myelofibrosis caused by COVID19, and should be considered a possible etiology added to the growing list of COVID19 sequelae.