title: Diagnostic markers for hyperemesis gravidarum: a systematic review and metaanalysis.
abstract: OBJECTIVE
  Currently, there is no consensus on the definition of hyperemesis gravidarum (HG; protracted vomiting in pregnancy) and no single widely used set of diagnostic criteria for HG. The various definitions rely on symptoms, sometimes in combination with laboratory tests. Through a systematic review, we aimed to summarize available evidence on the diagnostic value of biomarkers for HG. This could assist diagnosis and may shed light on the, as yet, not understood cause of the disorder.
  
  
  METHODS
  We searched Medline and Embase for articles about diagnostic biomarkers for either the presence or severity of HG or nausea and vomiting of pregnancy. We defined HG as any combination of nausea, vomiting, dehydration, weight loss, or hospitalization for nausea and/or vomiting in pregnancy, in the absence of any other obvious cause for these complaints.
  
  
  RESULTS
  We found 81 articles on 9 biomarkers. Although 65% of all studies included only HG cases with ketonuria, we did not find an association between ketonuria and presence or severity of HG in 5 studies reporting on this association. Metaanalysis, with the use of the hierarchical summary receiver operating characteristics model, yielded an odds ratio of 3.2 (95% confidence interval, 2.0-5.1) of Heliobacter pylori for HG, as compared with asymptomatic control subjects (sensitivity, 73%; specificity, 55%). Studies on human chorionic gonadotropin and thyroid hormones, leptin, estradiol, progesterone, and white blood count showed inconsistent associations with HG; lymphocytes tended to be higher in women with HG.
  
  
  CONCLUSIONS
  We did not find support for the use of ketonuria in the diagnosis of HG. H pylori serology might be useful in specific patients.
authors: Department of Obstetrics and Gynecology, Medical Centre Alkmaar, Alkmaar, the Netherlands.
authors: Maartje N
authors: MN
authors: Niemeijer
authors: Department of Obstetrics and Gynecology, Medical Centre Alkmaar, Alkmaar, the Netherlands.
authors: Iris J
authors: IJ
authors: Grooten
authors: Department of Obstetrics and Gynecology, Medical Centre Alkmaar, Alkmaar, the Netherlands.
authors: Nikki
authors: N
authors: Vos
authors: Department of Obstetrics and Gynecology, Medical Centre Alkmaar, Alkmaar, the Netherlands.
authors: Joke M J
authors: JM
authors: Bais
authors: Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, the Netherlands.
authors: Joris A
authors: JA
authors: van der Post
authors: Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, the Netherlands.
authors: Ben W
authors: BW
authors: Mol
authors: Department of Obstetrics and Gynecology, Academic Medical Center, Amsterdam, the Netherlands.
authors: Tessa J
authors: TJ
authors: Roseboom
authors: Department of Clinical Epidemiology, Biostatistics, and Bioinformatics, Academic Medical Center, Amsterdam, the Netherlands.
authors: Mariska M G
authors: MM
authors: Leeflang
authors: Department of Obstetrics and Gynecology, Medical Centre Alkmaar, Alkmaar, the Netherlands. Electronic address: r.c.painter@amc.uva.nl.
authors: Rebecca C
authors: RC
authors: Painter
mesh_terms: D015415:Biomarkers / Q000032:analysis; D006063:Chorionic Gonadotropin / Q000097:blood; D004958:Estradiol / Q000097:blood; D005260:Female; D016480:Helicobacter pylori / Q000302:isolation & purification; D006801:Humans; D006939:Hyperemesis Gravidarum / Q000175:diagnosis*; D007662:Ketosis / Q000150:complications; D020738:Leptin / Q000097:blood; D007958:Leukocyte Count; D008214:Lymphocytes / Q000378:metabolism; D011247:Pregnancy; D011374:Progesterone / Q000097:blood; D012720:Severity of Illness Index; D013963:Thyroid Hormones / Q000097:blood
chemical_list: D015415:Biomarkers; D006063:Chorionic Gonadotropin; D020738:Leptin; D013963:Thyroid Hormones; D011374:Progesterone; D004958:Estradiol
keywords: biomarker; diagnosis; hyperemesis gravidarum; nausea and vomiting; pregnancy