A follow-up on quantitative and qualitative olfactory dysfunction and other symptoms in patients recovering from COVID-19 smell loss.

BACKGROUND: Sudden smell loss is a specific early symptom of COVID-19, which, prior to the emergence of Omicron, had estimated prevalence of ~40% to 75%. Chemosensory impairments affect physical and mental health, and dietary behavior. Thus, it is critical to understand the rate and time course of smell recovery. The aim of this cohort study was to characterize smell function and recovery up to 11 months post COVID-19 infection. METHODS: This longitudinal survey of individuals suffering COVID-19-related smell loss assessed disease symptoms and gustatory and olfactory function. Participants (n=12,313) who completed an initial survey (S1) about respiratory symptoms, chemosensory function and COVID-19 diagnosis between April and September 2020, were invited to complete a follow-up survey (S2). Between September 2020 and February 2021, 27.5% participants responded (n=3,386), with 1,468 being diagnosed with COVID-19 and suffering co-occurring smell and taste loss at the beginning of their illness. RESULTS: At follow-up (median time since COVID-19 onset ~200 days), ~60% of women and ~48% of men reported less than 80% of their pre-illness smell ability. Taste typically recovered faster than smell, and taste loss rarely persisted if smell recovered. Prevalence of parosmia and phantosmia was ~10% of participants in S1 and increased substantially in S2: ~47% for parosmia and ~25% for phantosmia. Persistent smell impairment was associated with more symptoms overall, suggesting it may be a key marker of long-COVID illness. The ability to smell during COVID-19 was rated slightly lower by those who did not eventually recover their pre-illness ability to smell at S2. CONCLUSIONS: While smell ability improves for many individuals who lost it during acute COVID-19, the prevalence of parosmia and phantosmia increases substantially over time. Olfactory dysfunction is associated with broader persistent symptoms of COVID-19, and may last for many months following acute COVID-19. Taste loss in the absence of smell loss is rare. Persistent qualitative smell symptoms are emerging as common long-term sequelae; more research into treatment options is strongly warranted given that even conservative estimates suggest millions of individuals may experience parosmia following COVID-19. Healthcare providers worldwide need to be prepared to treat post COVID-19 secondary effects on physical and mental health.

[Conclusions of the first French workshop of standardization of anticardiolipin antibody determination associated with autoimmune pathology]. / Conclusions du 1er Atelier francais de standardisation du dosage des anticorps anticardiolipine associés à la pathologie autoimmune.

Anticardiolipine antibodies are a marker of the antiphospholipid syndrome. They are detected by Elisa. Despite its simplicity, the results obtained by this assay are not always reproducible despite several worldwide standardizations and the distribution of calibration sera by EN Harris. On 4 December 1992, the First French Anticardiolipin Antibodies Standardization Workshop was held in Paris. Eight coded standards were sent to 33 laboratories in France, one in Switzerland and one in Luxembourg. Some of them used several assays. Agreement between qualitative results was good for samples with high and moderate level of antibodies. But the results expressed in IgG antiphospholipid units were scattered, the interlaboratory coefficient of variation for each of the eight standards was higher than 70%, though the within-run coefficient of variation had a median value of 10%. Assays using bovine serum for the blocking buffer and for the dilution buffer seemed to give more reproducible results than assays using purified bovine serum albumin (p < 0.001). For only nine assays out of 38 which expressed results quantitatively, was a linear regression observed between the dilutions of a sample and the results expressed in IgG antiphospholipid units. Absence of linearity is an obstacle which must be overcome if we wish to compare quantitative results obtained by different laboratories.

[Chronic low back pain and lumbar rhizotomy]. / Lombalgie chronique et rhizolyse lombaire.

Spinal rhizotomy could be used for relief of chronic low back pain, in 287 selected patients suffering from facet joints. The procedure involves placing an electrode on close proximity to the posterior articular nerves to allow destruction by coagulation.

[Role of computed tomography in the diagnosis of complications of lumbar disk surgery]. / La place de l'examen tomodensitométrique dans le diagnostic des complications de la chirurgie discale lombaire.

Recurrence of symptomatology after diskectomy was investigated in 37 patients by computed tomography imaging. Local complications were mainly fibrous scar tissue formation and recurrence of disk lesions. Results showed the CT scan to be the most reliable exploratory procedure available at the present time, based on the quality of images obtained after intravenous iodized contrast injection.

[Vertebral artery loop and cervical pain]. / Boucle de l'artère vertébrale et cervicalgies.

Diagnosis of a vertebral artery loop in the transverse canal, suggested by a CT scan image, is dependent mainly on results of angiography (preferably computer assisted and by the venous route). This lesion is a differential diagnosis of a neuroma, when the cervical intervertebral foramen is enlarged.

Frequency of primary brain stem lesions after head injuries. A CT scan analysis from 186 cases of severe head trauma.

Analysis of level of brain stem dysfunction, evolution, and CT scan profile was made on 76 cases of head injuries with prolonged unconsciousness and without hemispheric focal lesion and midline shift on CT scan. Eleven cases were considered normal on CT scan. The CT scan aspect of primary brain stem lesion was identified in 31.5% of these series, and in 14.5% of all severe head traumas (186 cases), from which this series is taken. Primary and secondary CT scan profiles were observed whatever the clinical level of dysfunction and its evolution. Pontine lesions were mainly associated with haemorrhage in the brain stem and diffuse brain swelling; but minimal signs (cortical level) and benign outcome can also be related to axial haemorrhage. These results emphasize the frequency of primary brain stem lesions and the value of CT scan in head injuries.

[C.T. scan and traumatic intracranial haematoma without clinical signs (author's transl)]. / Tomodensitométrie et hématomes intracrániens post-traumatiques sans manifestation clinique.

Patients having sustained head injuries were investigated by computerized axial tomography, a few hours after trauma. 24 conscious patients had large traumatic lesions: epidural haematoma, acute subdural haematoma and cerebral attrition. 12 had no focal sign and were well conscious or very slightly drowsy. 12 were slightly drowsy and/or had focal signs but these signs were very discrete in contrast with the huge lesions seen on the CT Scan. This seems to confirm that an epidural haematoma expands very early after the head injury, and, in any case, that it does exist during the free interval. From a practical view point, computerized tomography may greatly improve the treatment of patients who, other-wise, would have been operated upon in comatose state. This study is not a prospective one, it does not lead to any statistical value. But it points out the usefulness of CT Scan after severe head injury especially of conscious patients, above all if there is a skull fracture.