title: Cerebral Hypoperfusion in Hereditary Coproporphyria (HCP): A Single Photon Emission Computed Tomography (SPECT) Study.
abstract: BACKGROUND
  Hereditary Coproporphyria (HCP) is characterized by abdominal pain, neurologic symptoms and psychiatric disorders, even if it might remain asymptomatic. The pathophysiology of both neurologic and psychiatric symptoms is not fully understood. Therefore, aiming to evaluate a possible role of brain blood flow disorders, we have retrospectively investigated cerebral perfusion patterns in Single Photon Emission Computed Tomography (SPECT) studies in HCP patients.
  
  
  METHODS
  We retrospectively evaluated the medical records of patients diagnosed as being affected by HCP. A total of seven HCP patients had been submitted to brain perfusion SPECT study with 99mTc-Exametazime (hexamethylpropyleneamine oxime, HMPAO) or with its functionally equivalent 99mTc-Bicisate (ECD or Neurolite) according with common procedures. In 3 patients the scintigraphic study had been repeated for a second time after the first evaluation at 3, 10 and 20 months, respectively. All the studied subjects had been also submitted to an electromyographic and a Magnetic Resonance Imaging (MRI) study of the brain.
  
  
  RESULTS
  Mild to moderate perfusion defects were detected in temporal lobes (all 7 patients), frontal lobes (6 patients) and parietal lobes (4 patients). Occipital lobe, basal ganglia and cerebellar involvement were never observed. In the three subjects in which SPECT study was repeated, some recovery of hypo-perfused areas and appearance of new perfusion defects in other brain regions have been found. In all patients electromyography resulted normal and MRI detected few unspecific gliotic lesions only in one patient. Discussion & Conclusions: Since perfusion abnormalities were usually mild to moderate, this can probably explain the normal pattern observed at MRI studies. Compared to MRI, SPECT with 99mTc showed higher sensitivity in HCP patients. Changes observed in HCP patients who had more than one study suggest that transient perfusion defects might be due to a brain artery spasm possibly leading to psychiatric and neurologic symptomatology, as already observed in patients affected by acute intermittent porphyria. This observation, if confirmed by other well designed studies aiming to demonstrate a direct link between artery spasm, perfusion defects and related symptoms could lead to improvements in HCP treatments.
authors.affiliation: Nuclear Medicine Unit, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo (FG), Italy. prof.gvalle@gmail.com.
authors.forename: Guido
authors.initials: G
authors.lastname: Valle
authors.affiliation: Department of Nephrology & Dialisis - Interregional Reference Center for the prevention, surveillance, diagnosis and treatment of porphyria, IRCCS Casa Sollievo della Sofferenza, San Giovanni Rotondo (FG), Italy. claudiocarmine.guida@tin.it.
authors.forename: Claudio Carmine
authors.initials: CC
authors.lastname: Guida
authors.forename: Michelangelo
authors.initials: M
authors.lastname: Nasuto
authors.forename: Manuela
authors.initials: M
authors.lastname: Totaro
authors.forename: Filippo
authors.initials: F
authors.lastname: Aucella
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Frusciante
authors.forename: Lazzaro
authors.initials: L
authors.lastname: Di Mauro
authors.forename: Adele
authors.initials: A
authors.lastname: Potenza
authors.forename: Maria
authors.initials: M
authors.lastname: Savino
authors.forename: Mario
authors.initials: M
authors.lastname: Stanislao
authors.forename: Teresa
authors.initials: T
authors.lastname: Popolizio
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Guglielmi
authors.forename: Vito Angelo
authors.initials: VA
authors.lastname: Giagulli
authors.forename: Edoardo
authors.initials: E
authors.lastname: Guastamacchia
authors.affiliation: Interdisciplinary Department of Medicine, Section of Internal Medicine, Geriatrics, Endocrinology and Rare Diseases, University of Bari "Aldo Moro", Bari, Italy. incenzo.triggiani@uniba.it.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Triggiani
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000098:blood supply* / Q000000981:diagnostic imaging* / Q000503:physiopathology; D046349:Coproporphyria, Hereditary / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D055815:Young Adult