Type B Lactic Acidosis Associated with High Risk Refractory Multiple Myeloma

Case Presentation

Ann Hematol Oncol. 2020; 7(1): 1280.

Type B Lactic Acidosis Associated with High Risk Refractory Multiple Myeloma

Motalo O* and Oczkowski S

Department of Medicine, McMaster University, Hamilton, ON, Canada

*Corresponding author: Motalo O, Department of Medicine, McMaster University, 1280 Main Street West, Room MDCL - 3101A, Hamilton, ON L8S 4K1, Canada

Received: December 14, 2019; Accepted: January 21, 2020; Published: January 28, 2020


Lactic Acidosis (LA) is a frequent cause of metabolic acidosis in hospitalized patients. Traditionally, LA has been divided into type A (hypoxic) and type B (non-hypoxic) with the latter being associated with malignancies. The exact mechanism of type B LA in malignancy is unknown, although several hypotheses have been proposed. To date most cases of type B LA have been described in patients living with solid tumors, leukemias, or lymphomas. We report the sixth known case of type B LA associated with refractory Multiple Myeloma (MM). This case report highlights well-described diagnostic challenges experienced by clinicians when approaching severe LA in patients with MM, as evidenced by frequent overtreatment of these patients with aggressive resuscitative measures without any gain in survival. The aim of our report is to facilitate earlier clinician recognition of type B LA secondary to MM through a review of the pathogenesis and approach to LA.

Keywords: Multiple myeloma; Refractory; Lactic acidosis; Type B; Approach


Lactic Acidosis (LA) is a frequent cause of metabolic acidosis in hospitalized patients [1,2]. Most commonly, hyperlactatemia results from tissue hypoxia (type A LA), although it can be caused by other metabolic derangements in the absence of hypoxia (type B LA) [1-3]. Treatment in either case is prompt recognition and management of the triggering condition(s) [1,2,4]. The link between type B LA and malignancy is well established; however, with respect to hematologic malignancies, it is best documented in leukemia and lymphoma [5]. The existence of type B LA in Multiple Myeloma (MM), a malignancy of plasma cells, has been described only in five case reports to date [5,11-14]. Failure to recognize progressive MM as a cause of a patient’s LA often leads to patient overtreatment with aggressive therapies and interventions, which are unlikely to alter the overall outcome and may increase suffering [5]. Thus, we describe a case of severe type B LA in a patient with refractory MM, focusing on the pathogenesis of LA and an approach to type B LA, in order to improve clinicians’ ability to promptly recognize this entity. Of note, our review is limited to L-LA, the isomer most commonly produced in humans; reviews of D-LA can be found elsewhere [6].

Case Presentation

A 63-year-old female with progressive back pain was diagnosed with lambda light chain MM in the spring of 2018. Initial diagnostic evaluation revealed the presence of end-organ damage, 60% plasma cells in the bone marrow, beta-2 microglobulin of 9.2mg/L, Lactate Dehydrogenase (LDH) of 293, as well as t(4;14) translocation and 17p deletion. According to the revised International Staging System for MM, this patient had high-risk disease. Interestingly, at the time of her diagnosis she was noted to have LA, which subsequently paralleled her disease course (Figure 1).