Long-term skeletal, cephalometric, and volumetric changes in two Helsinki bimaxillary face transplant patients.

Analysis of skeletal, cephalometric, and volumetric changes and occlusion during long-term follow-up was performed for two patients who underwent bimaxillary facial transplantation (FT). The study material consisted of the follow-up data of two bimaxillary composite FT performed in Helsinki University Hospital, one in 2016 and the other in 2018. Serial three-dimensional computed tomography scans obtained during follow-up (6 years for patient 1, 4 years for patient 2) were analyzed. The position of the maxilla remained stable in both patients. At 4 and 6 years, the changes in the anterior maxilla were ≤1 mm, while the anterior mandible had moved 2.6-4 mm anteriorly and the mandibular midline 0.4-3.7 mm to the left side. Patient 1 underwent re-osteosynthesis 4 months after transplantation due to mandibular non-union. Patient 2 had a sagittal mandibular osteotomy at 15 months after FT due to lateral crossbite and tension created by temporomandibular joint rotation. Thereafter both patients had a stable occlusion. A continuous bone volume reduction in the mandible was noticed in both patients (6% and 9% reduction of the transplanted volume). The volume of the transplanted maxilla decreased during the early postoperative period but increased back to the original transplanted volume during the follow-up.

Long-term quality of life after surgery of head and neck cancer with microvascular reconstruction: a prospective study with 4.9-years follow-up.

PURPOSE: The aim of this study was to evaluate the long-term health-related quality of life (HRQoL) of head and neck cancer patients with microvascular surgery. Surgical treatment causes great changes in patient HRQoL. Studies focusing on long-term HRQoL after microvascular reconstruction for head and neck cancer patients are scarce. METHODS: We conducted a prospective study of 93 patients with head and neck cancer and microvascular reconstruction in Helsinki University Hospital Finland. HRQoL was measured using the 15D instrument at baseline and after a mean 4.9-years follow up. Results were compared with those of an age-standardized general population. RESULTS: Of the 93 patients, 61 (66%) were alive after follow-up; of these, 42 (69%) answered the follow-up questionnaire. The median time between surgery and HRQoL assessment was 4.9 years (range 3.7-7.8 years). The mean 15D score of all patients (n = 42) at the 4.9-years follow up was statistically significantly (p = 0.010) and clinically importantly lower than at baseline. The dimensions of "speech" and "usual activities" were significantly impaired at the end of follow up. There was a significant difference at the 4.9-years follow-up in the mean 15D score between patients and the general population (p = 0.014). After follow up, patients were significantly (p < 0.05) worse off on the dimensions of "speech," "eating," and "usual activities." CONCLUSIONS: Long-term HRQoL was significantly reduced in the whole patient cohort. Speech and usual activities were the most affected dimensions in head and neck cancer patients with microvascular reconstruction at the end of the 4.9-years follow up.

Clinical Comparison of Scapular, Fibular, and Iliac Crest Osseal Free Flaps in Maxillofacial Reconstructions.

BACKGROUND AND AIMS:: This study compared the three most used composite flaps in maxillofacial reconstructions in our institute. PATIENTS AND METHODS:: Between 2000 and 2012, a total of 163 patients with mandibular, maxillary, and orbital defects received either scapular, fibular, or iliac crest osseal reconstructions in Helsinki University Hospital, Departments of Plastic Surgery and Maxillofacial Surgery. Data regarding the patient demographics, complications, and outcomes were analyzed. RESULTS:: There were 92 deep circumflex iliac artery flaps (56%), followed by 42 scapular (26%) and 29 fibular flaps (18%). The rate of flap loss was the highest in the deep circumflex iliac artery group (p = 0.001). Reconstructions using fibula were fastest (p = 0.001) and had lowest perioperative blood loss (p = 0.013). There were no significant differences in the number of early or late complications between the flaps, but donor site complications were more severe in deep circumflex iliac artery. Osteotomies as well as dental implants were safely performed in all flaps with equal results. CONCLUSION:: All three flaps of this study can be performed with awareness of the deep circumflex iliac artery flap being the least reliable alternative. The knowledge of the advantages and disadvantages of several osseal-free flap alternatives is beneficial in selecting the best suitable method for each individual patient requiring maxillofacial osseal reconstruction.

Dexamethasone in head and neck cancer patients with microvascular reconstruction: No benefit, more complications.

OBJECTIVES: Glucocorticoids are widely used in association with major surgery of the head and neck to improve postoperative rehabilitation, shorten intensive care unit and hospital stay, and reduce neck swelling. This study aimed to clarify whether peri- and postoperative use of dexamethasone in reconstructive head and neck cancer surgery is associated with any advantages or disadvantages. MATERIALS AND METHODS: This prospective double-blind randomized controlled trial comprised 93 patients. A total dose of 60mg of dexamethasone was administered to 51 patients over three days peri- and postoperatively. The remaining 42 patients served as controls. The main primary outcome variables were neck swelling, length of intensive care unit and hospital stay, duration of intubation or tracheostomy, and delay to start of possible radiotherapy. Complications were also recorded. RESULTS: No statistical differences emerged between the two groups in any of the main primary outcome variables. However, there were more major complications, especially infections, needing secondary surgery within three weeks of the operation in patients receiving dexamethasone than in control patients (27% vs. 7%, p=0.012). CONCLUSIONS: The use of dexamethasone in oral cancer patients with microvascular reconstruction did not provide a benefit. More major complications, especially infections, occurred in patients receiving dexamethasone. Our data thus do not support the use of peri- and postoperative dexamethasone in oropharyngeal cancer patients undergoing microvascular reconstruction.

Three-dimensional printing for restoration of the donor face: A new digital technique tested and used in the first facial allotransplantation patient in Finland.

BACKGROUND AND AIMS: Prosthetic mask restoration of the donor face is essential in current facial transplant protocols. The aim was to develop a new three-dimensional (3D) printing (additive manufacturing; AM) process for the production of a donor face mask that fulfilled the requirements for facial restoration after facial harvest. MATERIALS AND METHODS: A digital image of a single test person's face was obtained in a standardized setting and subjected to three different image processing techniques. These data were used for the 3D modeling and printing of a donor face mask. The process was also tested in a cadaver setting and ultimately used clinically in a donor patient after facial allograft harvest. RESULTS: and Conclusions: All the three developed and tested techniques enabled the 3D printing of a custom-made face mask in a timely manner that is almost an exact replica of the donor patient's face. This technique was successfully used in a facial allotransplantation donor patient.

Consistent expression of HGF and c-met in the perinatal lung.

BACKGROUND: Hepatocyte growth factor (HGF), an epithelial cell mitogen, has been shown to participate in normal lung development and in regeneration after lung injury. In human preterm infants, lower pulmonary HGF has been associated with more severe respiratory disease. OBJECTIVES: We studied the protein expression of HGF and its receptor c-met during the perinatal period in the human lung. METHODS: Immunohistochemistry for HGF and c-met was performed on lung tissues from autopsies of 4 fetuses, 5 preterm infants, 5 term infants, and 4 infants with bronchopulmonary dysplasia. RESULTS: Immunohistochemistry for HGF showed staining in all cases in mesenchymal cells (fibroblasts and cartilage cells). Additional staining was found in bronchial and distal airway epithelium. Immunohistochemistry for c-met showed staining in bronchial and distal airway epithelium, and in most cases in neutrophils. CONCLUSIONS: The consistent expression of HGF and c-met during the perinatal period supports a physiological role for HGF in human lung development.

Pulmonary vascular endothelial growth factor and Flt-1 in fetuses, in acute and chronic lung disease, and in persistent pulmonary hypertension of the newborn.

Respiratory distress syndrome (RDS) and development of bronchopulmonary dysplasia (BPD) are characterized by endothelial cell damage. Persistent pulmonary hypertension of the newborn (PPHN) is a disorder that alters the pulmonary microvasculature. Immunohistochemistry for VEGFA(165), an endothelial cell mitogen, and its receptor Flt-1, was performed on lung tissues from autopsies from four fetuses, three preterm infants, four term infants without primary lung disease, four infants with BPD, and four infants with PPHN. VEGF was measured in tracheal aspirates from 31 preterm infants, 5 intubated term infants without primary lung injury, and 12 infants with PPHN during the first 10 postnatal days, and from 8 infants with BPD. Immunohistochemistry for VEGF and Flt-1 was similar in fetuses, preterm infants, and term infants: for VEGF mostly in bronchial epithelium and alveolar macrophages, and for Flt-1 mostly in vascular endothelial cells and bronchial epithelial cells. In patients with BPD, and PPHN, staining for VEGF and Flt-1 appeared also in Type II pneumocytes. Preterm infants with more severe RDS had lower VEGF than those who recovered. The persistent expression of VEGF and Flt-1 during the fetal and neonatal period supports a physiological role for VEGF in human lung development. The lower pulmonary VEGF in preterm infants with more severe RDS may contribute to the pathophysiology of the acute lung injury. In BPD, the expression of VEGF in alveolar epithelium may represent a compensatory increase after the acute phase of the lung disease. In PPHN, that more cell types express VEGF and Flt-1, and the tendency toward a higher concentration of pulmonary VEGF may represent enhanced production of VEGF in response to impaired endothelial function.

Matrix metalloproteinases-2, -8, and -9 and TIMP-2 in tracheal aspirates from preterm infants with respiratory distress.

OBJECTIVES: Matrix metalloproteinases (MMPs) are a family endoproteinases that act in degradation of extracellular matrix and basement membranes. The development of bronchopulmonary dysplasia (BPD) is characterized by early pulmonary inflammation, increased microvascular permeability, and subsequently by disordered repair. The aims of our study were to characterize the presence and molecular weight forms of MMP-2, -8, and -9 and their specific inhibitor, tissue inhibitor of metalloproteinases (TIMP)-2, in lungs of preterm infants during the early postnatal period and to determine whether levels of these MMPs and TIMP-2 in tracheal aspirate fluid (TAF) are associated with acute or chronic lung morbidity of the preterm infant. METHODS: TAF samples were collected from 16 intubated preterm infants (gestational age 27.0 +/- 2.0 weeks; birth weight 875 +/- 246 g) during their first 5 postnatal days. The presence and molecular weight forms of MMPs and TIMP-2 were identified by Western immunoblotting, and their levels were evaluated by densitometric scanning. RESULTS: MMP-8 in TAF was higher in infants who needed treatment with surfactant (25.4 +/- 6.3 vs 10.6 +/- 1.5 arbitrary unit/secretory component of immunoglobulin A [AU/SC]) and in whom BPD developed (N = 6; 27.6 +/- 5.2 vs 15.1 +/- 5.0 AU/SC). TIMP-2 levels were lower in infants with initial arterial to alveolar oxygen tension ratios <0.22 (2.7 +/- 1.1 vs 16.8 +/- 7.4 AU/SC) and in infants needing mechanical ventilation for >1 week (5.2 +/- 2.1 vs 22.8 +/- 11.7 AU/SC). CONCLUSIONS: In preterm infants, an imbalance between pulmonary MMP-8 and TIMP-2 participates in the acute inflammatory process in respiratory distress syndrome and may contribute to the development of chronic lung injury.

Plasma cyclic guanosine monophosphate reflecting the severity of persistent pulmonary hypertension of the newborn.

The aim of the study was to examine the relationship between the plasma concentration of cyclic guanosine monophosphate (cGMP) and pulmonary pressure and hypoxia defined by oxygenation index (OI) in newborn infants with severe persistent pulmonary hypertension (PPHN) on inhaled nitric oxide (NO). In this prospective study, 18 newborn infants having Doppler ultrasound-diagnosed PPHN and treated with NO were investigated. The ratio of pulmonary artery to systemic artery pressure (PAP/SAP) and OI was assessed before treatment and at 0.5, 1, 12, and 24 h from the beginning of NO. At these time points, plasma concentrations of cGMP could be determined in 11 patients. The association of birth asphyxia as assessed by Apgar 1 min and 5 min and plasma cGMP before the NO treatment was examined. The initial median plasma concentration of cGMP was 37.3 pmol/ml (IQR 13.3-79.6). After the start of NO, cGMP increased significantly within 60 min (p = 0.003) and peaked at 12 h. Initial plasma cGMP was associated with Apgar score (1 and 5 min). OI decreased within 30 min of NO and PAP/SAP within 60 min. Persistent high PAP/SAP after 1 h of NO was associated with low cGMP concentration (r = 0.70, p = 0.02). We conclude that a significant increase in plasma cGMP is already evident after 60 min of NO therapy. This effect is accompanied by changes in oxygenation index and in pulmonary artery pressure. Initial plasma concentrations of cGMP were associated with hypoxia assessed as Apgar score.

Clara-cell secretory protein in preterm infants' tracheal aspirates correlates with maturity and increases in infection.

Clara-cell secretory protein (CCSP), produced primarily by Clara cells in the conducting airways, is the most abundant soluble protein in pulmonary lavage fluid. CCSP is thought to be an immunosuppressive or anti-inflammatory protein with protective functions in the respiratory tract against exaggerated inflammatory reactions. CCSP was measured in 98 tracheoalveolar fluid (TAF) samples from 24 preterm infants (gestational age, 27.9 +/- 2.3 weeks, birth weight 1,020 +/- 305 g) with respiratory distress syndrome during the first 2 postnatal weeks. The ratio of urea-N in serum and in TAF was used to correct for dilution of TAF samples. Concentration of CCSP in TAF when corrected for dilution increased from 3.6 +/- 11 microg/mL on day 1 to 29.6 +/- 6.9 microg/mL on day 14. CCSP correlated with gestational age. A negative correlation was found between CCSP and inspiratory oxygen concentration, and a positive correlation between CCSP and both arterial pH and base excess during the first 2 postnatal weeks. Infants with clinical and laboratory signs of infection had higher CCSP than noninfected infants, and a negative correlation was found between CCSP and leukocyte count during the first 2 postnatal weeks (all P < 0.05). We suggest that pulmonary CCSP correlates with both gestational and postnatal age, and increases in response to infection in infants with respiratory distress during the early postnatal period.

Phagocyte activation in preterm infants following premature rupture of the membranes or chorioamnionitis.

Phagocyte activation was studied in 48 preterm infants, gestational age 27.3 +/- 0.3 wk, birthweight 968 +/- 40 g, during the first postnatal week. Human neutrophil lipocalin as a marker of neutrophil activation was measured in plasma and tracheal aspirate fractions; and lysozyme, as a marker of monocyte and macrophage activation, in plasma. The concentration of plasma human neutrophil lipocalin was 69 (46-126) microg/l (median and quartiles), tracheal aspirate fraction fluid 213 (71-433) microg/l and plasma lysozyme 1337 (923-1764) microg/l. Infants born to mothers with premature rupture of the membranes or clinical chorioamnionitis (group A, n = 20) had significantly higher plasma [73 (58-151) vs 53 (38-108) microg/l; p=0.027], and tracheal aspirate fraction human neutrophil lipocalin [319 (129-540) vs 190 (57-324) microg/l; p = 0.019], and plasma lysozyme [1739 (1356-2021) vs 1140 (739-1557)microg/l; p=0.0001] than did infants whose mothers had intact membranes and who had no suspicion of infection (Group B, n = 28). In infants born to mothers receiving corticosteroids ante partum, correlations existed between time from treatment to delivery and plasma (r =0.322, p = 0.0256) and tracheal aspirate fraction human neutrophil lipocalin (r = 0.314, p = 0.0096).

Nitric oxide and hyperoxia in oxidative lung injury.

UNLABELLED: Therapy with inhaled nitric oxide is usually given with high concentrations of oxygen. As nitric oxide (NO) is a free radical and hyperoxia increases oxygen radical production, we examined the effect of short exposure to NO or oxygen (O2) or both, on free radical-mediated changes in macromolecules, i.e. lipids and proteins, in vivo. Wistar rats were exposed to > 95% O2 or 40 ppm NO, or both, for 6 h. Rats in 21% O2 served as controls. Lipid peroxidation was quantified as expired pentane, oxidative protein modification as carbonyl concentration, and pulmonary neutrophil accumulation as myeloperoxidase activity in the lungs. Hyperoxia for 6 h caused higher expired pentane (4.83 +/- 1.39 pmol/min/100 g) and protein carbonylation (15.91 +/- 2.49 nmol/mg) compared to controls (2.26 +/- 1.00 pmol/min/100 g, and 7.40 +/- 1.12 nmol/mg, respectively; both p < 0.05). After exposure to NO in air, protein carbonylation (14.50 +/- 5.44 nmol/mg) and myeloperoxidase activity (4.85 +/- 1.52 mU/mg) were higher than in controls (myeloperoxidase 2.49 +/- 0.56 mU/mg; both p < 0.05). NO with hyperoxia decreased pentane (2.56 +/- 1.51 pmol/min/ 100 g) and protein carbonylation (11.38 +/- 3.58 nmol/mg) compared to hyperoxia (both p < 0.05). CONCLUSION: In vivo, 6 h exposure to hyperoxia or to 40 ppm NO induces free radical-mediated lung injury. The combination of hyperoxia and 40 ppm NO significantly attenuates free radical-mediated effects in the lungs compared to hyperoxia or 40 ppm NO in air.

Extinction of rac1 and Cdc42Hs signalling defines a novel p53-dependent apoptotic pathway.

Apoptosis is a normal physiological process which eliminates cells that do not receive adequate extracellular signals. One of the pathways signalling apoptosis is controlled by the small GTPases of the Rho family, also involved in cell proliferation, differentiation and motility. Another major apoptosis signalling pathway involves the p53 tumour suppressor which is activated by a variety of stress and mediates growth arrest or apoptosis in normal cells. We show here that upon detachment from the extracellular matrix, fibroblasts undergo rapid apoptosis that can be rescued by constitutive activation of Rac1 and Cdc42Hs GTPases. Conversely, inhibition of Rac1 and Cdc42Hs efficiently triggers apoptosis in adherent cells. Interestingly, apoptosis is not observed in p53-/- cells either cultured in suspension or inhibited for Rac1 and Cdc42Hs activity. Moreover, Rac1 and Cdc42Hs extinction in normal cells activates endogenous p53. Using specific inhibitors of MAPK pathways, we demonstrate that, in our experimental system, p38 signals survival, while ERK activity is required for apoptosis. Our data constitute the first demonstration that Rac1 and Cdc42Hs control pathways that require simultaneous signalling through MAPK ERK and p53 to induce apoptosis.

Cyclooxygenase-2 in human perinatal lung.

Cyclooxygenases-1 and -2 are the key enzymes in the conversion of arachidonic acid to prostanoids. Cyclooxygenase-2 (COX-2) takes part both in inflammation and in control of cell growth. COX-2 immunohistochemistry was performed on lung tissues from autopsies, with four groups included: fetuses (n = 4, GA = 16.0 to 32.0 wk), preterm infants (n = 10, GA = 23.0 to 29.9 wk), term infants (n = 6, GA = 38.7 to 42.0 wk), and infants with bronchopulmonary dysplasia (BPD) (n = 4, GA = 28.9 to 30.7 wk). COX-2 staining occurred exclusively in the epithelial cells resembling type II pneumocytes in the alveolae, and in ciliated epithelial cells in the bronchi. In fetuses, moderate intensity alveolar staining was seen in 90-100% cells lining the alveolar epithelium. In preterm infants, high intensity alveolar staining was seen in a scattered pattern. In term infants, the alveolar staining was also scattered, but with a lower proportion of positive cells. In BPD no staining appeared in alveolar epithelial cells. The most intense bronchial staining was found in fetuses and the least intense in term infants; staining was also seen in BPD. COX-2 is present in human perinatal lung from the gestational age of 16 wk, in a changing pattern. We suggest that COX-2 may, in addition to participating in inflammation, also play a developmental role in the perinatal lung.

Comparative efficiencies of different non-toxic microalgal diets in detoxification of PSP-contaminated oysters (Crassostrea gigas Thunberg).

Experimental PSP contamination of adult Pacific oysters (Crassostrea gigas) by the toxic dinoflagellate Alexandrium minutum Halim (120 cells.mL-1 continuously maintained in each flume) was carried out in a recirculated seawater system to obtain toxin levels above the safety threshold. In these conditions, 150 to 300 micrograms STX.eq.100 g-1 of shellfish tissues were produced at 16 degrees C within 8 to 15 days, corresponding to field values observed along French coasts. Diets based on non-toxic flagellates or diatoms were then used to detoxify the contaminated oysters. Despite large individual variations in toxin levels at the end of the contamination period, detoxification times were of the same order of magnitude (3 to 4 days), reaching a toxin level equal to or less than the safety threshold. These variations were most likely related to marked individual variability in valve and/or clearance activities. No significant differences in detoxification rates were found when oysters were fed Isochrysis galbana, Tetraselmis suecica, Thalassiosira weissflogii, or Skeletonema costatum. The different biochemical compositions of each algal species appeared to have no significant effect on detoxification rates. GTX2/GTX3 were the dominant compounds found in shellfish tissues during depuration, whereas C toxins were quite low (< 2 micrograms STX.eq.100 g-1) and STX or NeoSTX undetectable. These results do not suggest any bioconversion of paralytic toxins but indicate good correlation between the toxin composition of Alexandrium and oyster tissues.

Toxigenic saprophytic fungi in marine shellfish farming areas.

Toxigenic saprophytic fungi were isolated from samples of shellfish, sediment and seawater obtained from marine shellfish farming areas. The 456 strains identified included 12 different genera, with a clear predominance (68%) of Penicillium, Aspergillus, Trichoderma and Cladosporium. To assess the risk of poisoning due to the presence of these fungi in shellfish farming areas, the strains were cultured in liquid medium, filtered, and tested on larvae of Artemia salina, a small crustacean highly sensitive to mycotoxins. Thirty-five point five percent of the strains proved active with this test. This study confirms the existence of fungi in shellfish farming areas, as suggested by our earlier work showing that filter-feeding shellfish accumulate toxic metabolites of fungal origin. The presence of fungi in the marine environment represents a real risk of poisoning through the consumption of contaminated shellfish.

Anti-apoptotic activity of p53 maps to the COOH-terminal domain and is retained in a highly oncogenic natural mutant.

The tumour suppressor p53 plays a complex role in the regulation of apoptosis. High levels of wild type p53 potentiate the apoptotic response, while physiological range, low levels of the protein have an anti-apoptotic activity in serum starved immortalized fibroblasts. Here we report that primary fibroblast-like cells that show normal growth control are also efficiently protected from apoptosis by the endogenous p53 activity. The capacity to inhibit apoptosis is not restricted to the wild type protein: the R-->H175 p53 mutant fully retains the anti-apoptotic activity of the wild type p53, providing a possible explanation for its high oncogenicity. Using a series of point and deletion mutants of p53 under the control of tetracycline-regulated promoter we show that certain mutants, like the wild type, protect cells at low levels but lead to apoptosis when overexpressed. This latter effect is lost upon deletion of a proline-rich domain in the NH2 part of the protein. The anti-apoptotic activity can be mapped to the extreme carboxy-terminal part of the protein and is therefore independent of other well characterized p53 activities. Our results add a new level of complexity to the network of interactions mediated by p53 in normal physiology and pathology.

Vascular endothelial growth factor in human preterm lung.

Endothelial cell damage is characteristic for respiratory distress syndrome and development of chronic lung disease. Vascular endothelial growth factor (VEGF) is an endothelial mitogen that takes part in the growth and repair of vascular endothelial cells. We measured VEGF in 189 tracheal aspirate samples (TAF), and in 24 plasma samples from 44 intubated preterm infants (gestational age, 27.3 +/- 2.0 wk; birth weight, 962 +/- 319 g) during their first postnatal week. VEGF in TAF increased from 25 +/- 12 pg/ml (mean +/- SEM) on Day 1 to 526 +/- 120 pg/ml on Day 7 (mean concentrations, 106 +/- 25 pg/ml on Days 1 to 3 and 342 +/- 36 pg/ml on Days 4 to 7). In plasma, mean concentration of VEGF during the first week was 48 +/- 6 pg/ml, with no increase observed. In TAF, higher VEGF was found in patients born to mothers with premature rupture of the membranes, or chorionamnionitis, whereas preeclampsia of the mother was associated with lower VEGF (all p < 0.05). In TAF, no correlations existed between VEGF and gestational age or birth weight, but a correlation existed between lecithin/sphengomyelin ratio and VEGF (p < 0.05). During Days 4 to 7 patients developing bronchopulmonary dysplasia (BPD) had lower VEGF in TAF than did those surviving without BPD (235 +/- 31 versus 383 +/- 50; p < 0.05). VEGF increased rapidly in the lungs of the preterm infant during the first days of life. VEGF may be indicative of pulmonary maturity and may participate in pulmonary repair after acute lung injury.

[Mycoplasma pneumoniae meningoencephalitis]. / Méningoencéphalite à Mycoplasma pneumoniae.

BACKGROUND: Severe central nervous system diseases, such as encephalitis, have been reported in association with Mycoplasma pneumoniae infections. CASE REPORT: After an ENT infection, a 9-year-old boy with Down's syndrome developed encephalitis revealed by an acute alteration in consciousness. Head computed tomography showed, after 2 weeks, an infiltration in the basal ganglia region. The diagnosis of Mycoplasma pneumoniae encephalitis was made; recovery was complete in a few weeks. CONCLUSION: Mycoplasma pneumoniae infection should be considered in all cases of acute encephalopathy; yet the pathogenesis of the disorder is unknown and the treatment uncertain.