Case Presentation: A 78 y/o M with PMH of papillary thyroid CA, BPH, and primary myelofibrosis of the bone marrow (has JAK2 mutation, leukocytosis and thrombocytosis, has not received therapy to date) presented with 8 day history of early satiety, fatigue, and new increasing ascites.
An inItial diagnostic paracentesis showed SAAG = 1.1, total protein = 4.0, WBC 3000, PMN 37%, Lymph 12%, Mono 20%, Eos 6%, Baso 9%, metamyelo 5%, myelo 9%. He was initiated on ceftriaxone and albumin for Spontaneous Bacterial Peritonitis (SBP) as the PMN count was above 250, although this did not fit the clinical picture as he had no prior history of cirrhosis nor did his hepatomegaly fit with a diagnosis of cirrhosis. His serum albumin was 3.8-4.0 therefore his presentation is not consistent with nephrotic syndrome. Cardiac etiology was entertained as he was found to have an LVEF of 40% on TTE, however no right heart dysfunction was noted and his BNP was noted to be 30, which suggested against cardiac ascites. The patient’s hematologist was updated about the patient’s admission and noted extramedullary hematopoiesis can be a cause of ascites. Repeat large volume paracentesis was performed.
Repeat studies showed SAAGs of 1.0 and 0.9 with high protein, consistent with exudative effusion. A CT abdomen/pelvis was obtained
which did not show evidence of primary or metastatic cancer to the liver, although peritoneal implants could not be evaluated because his renal function precluded IV contrast. Serum GI tumor markers were all negative. Fluid cytology showing atypical cells most likely reparative/reactive, although neoplasia could not be excluded.
An adenosine deaminase level in his ascitic fluid was noted to be positive at 15 (normal < 7.6). A PPD was negative. A quantiferon gold test was indeterminate. A large volume paracentesis was performed to provide samples for cytology, AFB culture, as well as TB nucleic acid amplification; the latter returned negative. The patient underwent therapeutic paracentesis with removal of 4L of ascites with temporary improvement, but reaccumulated the fluid within 24 hours. Given exudative nature of his ascites, diuretics were not utilized. Serial paracenteses were discussed as primary management, though even that was not recommended given rapid reaccumulation. The patient was discharged home with outpatient follow-up including with his hematologist to follow up on pending AFB cultures and fluid cytology. Several days after discharge, the patient's ascites fluid pathology returned positive for neoplastic cells (myeloid precursors, erythroid precursors and megakaryocytes suggestive of extramedullary hematopoiesis), consistent with known history of Jak2 positive chronic myeloproliferative disorder.
Discussion: Extramedullary hematopoiesis involving the peritoneum has been reported to cause ascites in several patients. In case reports of peritoneal implants bone marrow precursor cells such as megakaryocytes were noted in the ascitic fluid, which our patient was noted to have as well. Beyond treatment of the underlying malignancy, there are limited treatment options: Given the exudative nature of this type of ascites, diuretics are not indicated. Paracentesis can provide symptomatic relief, but this can be limited by reaccumulation, which was rapid in our patient’s case.
Conclusions: In patients with primary bone marrow disorders, consider extramedullary hematopoiesis as an etiology of new-onset ascites.