title: Central lactic acidosis, hyperventilation, and respiratory alkalosis: leading clinical features in a 3-year-old boy with malignant meningeal melanoma.
abstract: Meningeal tumors are extremely rare in children and are diagnostically as well as therapeutically challenging. Among the least common types of malignancies in childhood is malignant melanoma, counting for less than 1% of pediatric tumors. Due to the rarity and the wide spectrum of appearance, initial clinical features may be misleading. A 3-year-old boy was referred to our hospital with symptoms of hyperventilation, dyspnoea, tachycardia, respiratory alkalosis, inarticulate speech, and fatigue. Measurement of pH in cerebrospinal fluid (CSF) yielded central lactic acidosis despite alkalosis in peripheral blood. Diagnostic imaging procedures as well as histology and immunohistochemistry revealed the diagnosis of a malignant meningeal melanoma. We hypothesize that central lactate production of the tumor nests might have induced central acidification, thus inducing hyperventilation by stimulation of central chemoreceptors. This case is a model example of the key role of central pH as an inducer/suppressor of ventilation in humans and illustrates the critical importance of central pH for regulating both ventilation and acid-base homeostasis. Thus, pH of CSF should be measured whenever a malignant brain tumor is suspected.
authors.affiliation: Hospital for Children and Adolescents, University of Leipzig, Oststrasse 21-25, 04317, Leipzig, Germany. Susann.blueher@medizin.uni-leipzig.de
authors.forename: Susann
authors.initials: S
authors.lastname: Blüher
authors.forename: Manuela
authors.initials: M
authors.lastname: Schulz
authors.forename: Uta
authors.initials: U
authors.lastname: Bierbach
authors.forename: Jürgen
authors.initials: J
authors.lastname: Meixensberger
authors.forename: Ralf-Bodo
authors.initials: RB
authors.lastname: Tröbs
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Hirsch
authors.forename: Ralf
authors.initials: R
authors.lastname: Schober
authors.forename: Wieland
authors.initials: W
authors.lastname: Kiess
authors.forename: Werner
authors.initials: W
authors.lastname: Siekmeyer
mesh_terms: D000140:Acidosis, Lactic / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D000472:Alkalosis, Respiratory / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D002675:Child, Preschool; D003937:Diagnosis, Differential; D017809:Fatal Outcome; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006985:Hyperventilation / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D019344:Lactic Acid / Q000097:blood*; D008279:Magnetic Resonance Imaging; D008297:Male; D008545:Melanoma / Q000097:blood / Q000150:complications* / Q000175:diagnosis; D008577:Meningeal Neoplasms / Q000097:blood / Q000150:complications* / Q000175:diagnosis
chemical_list: D019344:Lactic Acid