[From when on can fungi be identified in nasal mucus of humans?]

BACKGROUND

Fungal spores are frequent in air and their occurrence in the nasal mucus appears to be a common finding within the adult population, as we were able to show in recent studies. 91,3 % of CRS patients but also healthy controls grew positive fungal cultures out of their nasal mucus. The potential role of fungal elements in nasal mucus for the pathogenesis of CRS, with or without polyposis, is currently investigated intensely and discussed very controversially. However, it was still unknown, as of when fungi could be cultured from nasal mucus in humans. We attempted to identify this point of time, in the nasal mucus of neonates.

METHODS

In our study we examined nasal mucus from 30 neonates immediately after birth, on the first and fourth day post partum, and after two and four months of life. The samples obtained with sterile cotton swabs were cultured on agar plates. Fungal cultures were identified either conventionally by microscopy or with molecular techniques. To show whether fungi in nasal mucus of newborns were acquired by contamination during birth, mucus of the maternal vagina was examined as well.

RESULTS

Just after birth we found in 6 of 30 (20 %) of our neonates positive fungal cultures out of their nasal mucus, in 3 of them Candida albicans, probably due to contamination passing the maternal vagina as cultures of vaginal mucus of their mothers were positive for Candida albicans too. Positive fungal cultures were obtained in 2 of 29 (7 %) neonates on the second and in 4 of 26 (15 %) neonates on the fifth day of life. In all our cases initial presence in nasal mucus contamination just after birth or on the second day of life was limited to one day only. None of the 12 of 30 (40 %) neonates with positive fungal cultures from nasal mucus in the first 5 days of life showed clinical symptoms of nasal fungal colonisation. Besides Candida albicans, Penicillium sp., Cladosporium cladosporioides, Acremonium polychromum, Beauveria bassiana and Epicoccum nigrum could be detected in the first 5 days of life. After the second month of life, examination of nasal mucus yielded positive fungal cultures in 8 of 11 (72 %), after four months even 17 of 18 (94 %) of babies, with a wide array of different species.

CONCLUSIONS

Fungi can be cultured from nasal mucus as soon as contact with the environmental air exists. Furthermore, a transfer of fungi from the mother's birth canal into the nose during birth is possible. Presence of fungal spores is common but not persistent in the nose of babies in the first days of life. However, after four months the situation is similar to the one in adults: fungal cultures can be obtained from almost everyone's nose. Therefore fungal spores must be considered a normal content of nasal mucus. Fungal spores are inhaled with every breath, some stick to the mucus, are transported to the nasopharynx and swallowed. This does not cause any clinical symptoms and is therefore not a pathological finding at all.

Direkte MR-Arthrographie des Handgelenkes - Wertigkeit im Nachweis von Komplett- und Partialdefekten der intrinsischen Ligamente und des TFCC im Vergleich zur Arthroskopie

PURPOSE

To assess the value of two-compartment magnetic resonance (MR) wrist arthrography in comparison with diagnostic arthroscopy for the evaluation of defects of the triangular fibrocartilage complex (TFCC) and intrinsic ligaments in patients with refractory wrist pain. The direct MR arthrographies were evaluated following arthroscopic classification with consideration of complete and partial defects. The distinction between these types of lesions has clinical implications for treatment procedures such as cast immobilization, arthroscopic debridement, surgical repair or partial intercarpal arthrodesis.

MATERIALS AND METHODS

Seventy-five patients (25 female, 50 males, mean age 38.3 years) who suffered from refractory wrist pain without radiography evidence of carpal instability underwent two-compartment wrist MR arthrography. Under aseptic conditions a solution of gadopentate dimeglumine and iodinated contrast agent (concentration 2.5 mmol/l) was injected into the radiocarpal and midcarpal joints under fluoroscopy guidance. Using a scanner of 1.5 T field strength and a wrist-coil following sequences were acquired: coronary and sagittal T (1)-weighted spin-echo (SE) sequences (TR 500 ms, TE 25 ms, matrix 512 x 512.3 mm) and coronary fast low angle shot (FLASH) 3D sequences (TR 24 ms, TE 11 ms, matrix 256 x 256, 1.5 mm, flip angle 50 degrees). All patients underwent subsequent arthroscopy of the wrist. The direct MR arthrographies were evaluated retrospectively by two observers experienced in the diagnosis of wrist pathology. They were not aware of the clinicial, arthrographic and arthroscopic findings. Pathology of the scapholunate ligament was classified according to the guidelines of the German Society of Hand Surgery (DGH), lesions of the lunotriquetral ligament according to Hempfling and lesions of the TFCC according to Palmer.

RESULTS

Twenty-five complete and 47 partial defects were detected arthroscopically (TFCC: 21/20, scapholunate ligament: 3/18, lunotriquetral ligament: 1/9). The TFCC showed a higher prevalence for degenerative lesions (11 type 2C-lesions and 20 type 2A/B lesions) than for traumatic lesions (5 type 1A lesions, 5 type 1D lesions). For direct MR arthrography, the obtained sensitivities and specificities in assessing complete defects were 96 % and 99.6 % (T (1)-weighted SE) and 92 % and 100 % (FLASH 3D), respectively. For all partial defects, sensitivities and specificities were 68.1 % and 93.3 % (T (1)-weighted SE) and 63 % and 96.1 % (FLASH 3D), respectively. For depicting partial defects of the scapholunate ligament the T (1)-weighted SE sequence (83.3/95.5 %) was superior to the FLASH 3D sequence (64.7/96.6 %), p < 0.05. For the evaluation of the TFCC (T (1)-weighted SE: 65/94.4 %, FLASH 3D: 70/94.6 %) and the lunotriquetral ligament (T (1)-weighted SE: 44/89.4 %, FLASH 3D: 44 /96.7 %), direct MR arthrography showed an insufficient correlation with arthroscopy.

CONCLUSION

Direct MR arthrography proved to be of equal value compared with diagnostic arthroscopy in detecting complete defects of the intrinsic ligaments and the TFCC. The method has the potential of replacing diagnostic arthroscopy for the evaluation of the intrinsic ligaments and the TFCC. The T (1)-weighted SE sequence appeared to be superior to the FLASH 3D sequence in evaluating partial defects of the scapholunate ligament. Direct MR arthrography did not reliably detect partial defects of the TFCC and the lunotriquetral ligament.

[The basidiomycete Schizophyllum commune in paranasal sinuses]

In the last fifty years, only 22 medical cases involving the basidiomycetous fungus Schizophyllum commune were reported. In a period of three years we have examined 270 patients suffering from chronic rhinosinusitis as well as from mycoses (fungus balls) within the paranasal sinuses. Either nasal mucus or fungal concrement from the sinuses were cultured and the resulting cultures identified microscopically. In cases, where a reliable identification of the fungi was not possible, DNA was extracted for molecular examination. The internal transcribed spacer (ITS) region of the ribosomal gene-cluster was amplified with fungus specific primers and sequenced thereafter. In addition, DNA of all fungi growing with sterile white mycelium was amplified with the primer pair scom1/scom2r, which is specific for S. commune. Altogether, within a three years period S. commune was isolated in twelve patients. It can be assumed, that with the presented methods S. commune will be found much more frequently in patients suffering from diseases of the nasal sinuses.

[Respiratory epitheloid adenomatoid hamartoma of the nasal cavity--case report and review of the literature]

BACKGROUND

Hamartomas are tumour-like malformations, resulting from excessive proliferation of otherwise normal local tissue components. Hamartomas of the nasal cavity and paranasal sinuses are relatively rare, especially respiratory epithelial adenomatoid hamartomas. This benign lesion is characterized by a glandular proliferation originating from the surface of the respiratory epithelium. In the German speaking literature this entity has not been described before.

PATIENT AND RESULTS

We report the case of a 51-year-old white female, presenting with a respiratory epithelial adenomatoid hamartoma of her left nasal cavity. The patient suffered from nasal obstruction. The CT scan showed a soft tissue like lesion obstructing the patient's left choana. After local resection of the tumour, which originated from the superior turbinate through functional endoscopic sinus surgery the patient's symptoms were gone. Follow-up after six months showed no evidence of recurrence.

CONCLUSION

The histopathological differential diagnosis of respiratory epithelial adenomatoid hamartomas includes inverted papilloma and adenocarcinoma. Therefore the histological recognition of these hamartomas impacts on therapy. Misinterpretation as a true neoplasm may result in unnecessarily radical surgery. Local surgical resection is the treatment of choice for this lesion.

[Incidence and detection of fungi and eosinophilic granulocytes in chronic rhinosinusitis]

BACKGROUND

Chronic Rhinosinusitis (CRS) is the most common chronic disease in the United States. Though for Europe no data are available, we have to assume that the situation is similar. Although the disease is defined very well by clinical symptoms, up to date the etiology and pathogenesis of chronic rhinosinusitis are unknown. CRS is considered to be multifactorial, with thickening of the mucosa and formation of polyps as an end stage of the disease. Treatment of choice includes corticosteroids and/or endoscopic or microscopic surgery. Antibiotics only help, if there is an acute bacterial exacerbation of the disease. They are not able to cure chronic rhinosinusitis per se. In 1999 Mayo Clinic researchers published data concerning the incidence of so-called "allergic" fungal sinusitis (AFS) in their patients suffering from chronic rhinosinusitis, demonstrating the majority of patients investigated presenting those criteria. Our own initial data from 2000 confirmed their findings.

MATERIAL AND METHODS

In an open prospective study fungal cultures were obtained from nasal mucus of 238 consecutive patients suffering from CRS. As control group acted 23 members of our staff, who did not show any evidence for CRS. In addition, in 37 CRS patients surgical specimens (mucus and tissue) were investigated histologically for evidence of eosinophilic granulocytes and fungal elements.

RESULTS

Using new techniques for fungal detection in culture and histology as proposed by Mayo Clinic researchers, positive detection of fungal cultures of the mucus of our CRS patients developed from 7 % in the past up to 87 % at present. 91.3 % of our control group yielded a positive result in fungal culture. Histologically, eosinophilic clusters were evident in 94.6 % and fungal elements were detected in 75.5 % within the mucus of 37 surgical CRS patients. Overall, 89.2 % of our surgical patients thus fulfilled the criteria of so-called AFS. Compared to our findings in the past, our latest results show an increase of 80 % in detection of fungal elements in our CRS patients. In all we were able to identify 654 positive fungal cultures in 238 CRS patients and 23 healthy controls respectively. 88 different genera grew, with 2.4 different species per patient and 3.1 different species per healthy control, on average.

CONCLUSION

Utilizing new techniques of fungal culturing out of the mucus of CRS patients and healthy controls, the number of positive fungal cultures increased dramatically from 7 % to 87 % in our patients and 91.3 % in healthy controls respectively. To obtain these results it is crucial to perform special techniques of mucus sampling and pretreatment for culturing as well as for histological investigations. Our results show, that with suitable techniques fungi can be identified in almost everybody's nose, CRS patient or healthy. When inhaled, those airborne fungi are only "in transit" through the nose. Positive fungal cultures from nasal secretion therefore have to be considered normal findings. The reason for this delayed recognition has to be attributed to our inadequate methods in the past. In contrast to healthy controls, clusters of eosinophils and fungal elements are present simultaneously within the mucus of CRS patients and appear to be a marker of the disease.

Fungal biodiversity--as found in nasal mucus

The biodiversity of fungi isolated from the nasal mucus of patients suffering from chronic rhinosinusitis and from healthy persons was monitored over 28 months. Mucus samples were obtained by flushing the noses of patients with saline or by endoscopic sinus surgery. Fungi from mucus were cultivated on agar plates. Identification was performed microscopically and by polymerase chain reaction with subsequent sequencing of the ribosomal internal transcribed spacer region. Altogether, 619 strains of fungi were cultivated from 233 subjects. Eighty-one species were identified, with a maximum of nine different species per person. The most prevalent isolates belonged to the genera Penicillium, Aspergillus, Cladosporium, Alternaria and Aureobasidium. Whereas Aspergillus and Penicillium spp. occurred in more or less the same numbers throughout the year, Cladosporium spp., Alternaria spp. and Aureobasidium pullulans showed a significantly higher occurrence during late summer and early autumn.

Long-term results after posterior fixation of thoraco-lumbar burst fractures

Current concepts of treating thoraco-lumbar burst-compression injuries are based on posterior transpedicular fixation techniques which are angular stable. However, the long-term results of this approach are controversial due to inconsistent reports and due to a paucity of data on late outcome. In the present study we analyzed 50 patients retrospectively who had an unstable burst-compression injury at T 11-L 2 (type A 3 according to Magerl) without a neurological deficit. All fractures were stabilized by an internal fixator either with or without transpedicular spongiosa grafting. Patients were treated between 1991 and 1997. Follow-up times ranged from 36 to 103 months. Follow-up examinations collected occupational, subjective and clinical data (activity score, Hannover spine score) and included radiographic measurements. The latter were used to calculate the sagittal index (SI) which measures deformities of the fractured vertebral body, and the sagittal plane kyphosis (SPK) which additionally describes an eventual destruction of the affected intervertebral disc. Compared with the preinjury status, the percentage of subjects who were able to do physical labor was reduced by half at follow-up, and four times as many patients had a permanent disability. Correspondingly, activity scores and Hannover spine scores declined significantly. After the initial surgical correction SI remained stable until follow-up, whereas SPK decreased again towards pre-operative values indicating a progressive deformity of the intervertebral disc space. Clinical results did not correlate with radiographic results, and neither the time until follow-up nor the type of fracture n or the use of transpedicular bone grafting affected clinical or radiographic results significantly.

Transcription factor Sp3 is regulated by acetylation

Sp3 is a ubiquitous transcription factor closely related to Sp1. Previous analyses showed that, unlike Sp1, Sp3 fails to activate transcription in certain promoter settings. This is due to the presence of an inhibitory domain located between the second glutamine-rich activation domain and the DNA-binding domain. To further analyze the transcriptional properties of Sp3, we have expressed and purified recombinant Sp3 and Sp1 as epitope-tagged proteins from stable transfected insect cells. We found that Sp3 does act as a strong activator similar to Sp1 in an in vitro transcription assay using Sp1/Sp3-depleted HeLa nuclear extract. However, on the same promoter Sp3 is almost inactive when transfected into cells. Mutational studies demonstrate that a single lysine residue is responsible for the low transcriptional activity of Sp3 in vivo. We show that Sp3, but not a mutant of Sp3 that lacks this lysine residue, is highly acetylated in vivo. Our results strongly suggest that the transcriptional activity of Sp3 is regulated by acetylation. The consequences of acetylation for the activity of Sp3 are discussed.

Regulation of mu-opioid receptor gene transcription by interleukin-4 and influence of an allelic variation within a STAT6 transcription factor binding site

Morphine and the endogenous opioid peptide beta-endorphin exert neuromodulatory as well as immunomodulatory effects, which are transduced by mu-opioid receptors. In this report we show that stimulation with interleukin-4 induces mu-opioid receptor transcripts in human primary blood cells (T cells and polymorphonuclear leukocytes), immune cell lines (Raji, U-937, and HMEC-1), and dendritic cells. In nonstimulated immune cells this gene is silent. In addition, mu receptor transcription is up-regulated by interleukin-4 in cultures of primary rat neurons. Transient transfection experiments in Raji and SH SY5Y neuronal cells with human and rat reporter gene constructs linked the interleukin-4 effect directly to cis-active mu receptor promoter elements located at nucleotide -997 on the human gene and nucleotide -727 on the rat gene. The interleukin-4 response elements function orientation independently. They bind STAT6 transcription factors as shown by electrophoretic mobility shift assays. In the human gene, a single nucleotide polymorphism within the interleukin-4 response element reduces the trans-activating potential of this element by 50%, which may affect the phenotype of persons carrying this variation. These findings provide a molecular basis for understanding bidirectional interactions between the opioid system and the immune system.

Complex phenotype of mice homozygous for a null mutation in the Sp4 transcription factor gene

BACKGROUND

Sp4 is a zinc finger transcription factor which is closely related to Sp1 and Sp3. All three proteins recognize the same DNA elements and can act as transcriptional activators through glutamine-rich activation domains. Unlike Sp1 and Sp3, which are ubiquitous proteins, Sp4 is highly abundant in the central nervous system, but also detectable in many other tissues.

RESULTS

We have disrupted the mouse Sp4 gene by a targeted deletion of the exons encoding the N-terminal activation domains. Sp4 knockout mice show a complete absence of Sp4 expression. They develop until birth without obvious abnormalities. After birth, two-thirds die within 4 weeks. Surviving mice are growth retarded. Male Sp4null mice do not breed. The cause for the breeding defect remains obscure since they show complete spermatogenesis. In addition, pheromone receptor genes in the vomeronasal organ appear unaffected. Female Sp4null mice have a smaller thymus, spleen and uterus. In addition, they exhibit a pronounced delay in sexual maturation.

CONCLUSIONS

The phenotype of the Sp4null mice differs significantly from those described for Sp1-/- and Sp3-/- mice. Thus, the structural similarities, the common recognition motif and the overlapping expression pattern of these three transcription factors do not reflect similar physiological functions.

Development of molecular methods for identification of Schizophyllum commune from clinical samples

In the last 50 years, to our knowledge, only 16 cases of diseases caused by Schizophyllum commune in humans have been reported. Within only 6 months, we found four isolates of this basidiomycetous fungus, obtained from patients suffering from chronic sinusitis. The cultures of the isolated fungi showed neither clamp connections nor fruiting bodies (basidiocarps), which are distinctive features for S. commune, but fast-growing cottony white mycelium only. This was harvested, and DNA was extracted. The internal transcribed spacer region of the ribosomal DNA (rDNA) was amplified with fungus-specific primers, and the PCR products were sequenced. Two strains of S. commune, collected from branches of a European hornbeam (Carpinus betulus) and a tree of heaven (Ailanthus altissima), respectively; four specimens from the herbarium of the Institute of Botany, Karl-Franzens-University Graz; and two strains from internationally known culture collections (CBS 340.81 [ATCC 44201] and CBS 405.96) were investigated in the same way. The sequence data of all strains were compared and showed homology of over 99% in this 660-bp-long fragment of rDNA. With these results, a map of restriction enzyme cutting sites and a primer set specific for S. commune were created for reliable identification of this human pathogenic fungus.

Regulation of the Clara cell secretory protein/uteroglobin promoter in lung

Clara cell secretory protein/uteroglobin (CCSP/UG) is specifically expressed in the conducting airway epithelium of the lung in a differentiation-dependent manner. The proximal promoter region of the rodent CCSP/UG gene directs Clara cell specificity. Previously, it was shown that the forkhead transcription factors HNF-3 alpha and beta and the homeodomain factor TTF-1 are important transcription factors acting through this region, suggesting that they contribute to cell specificity of the CCSP/UG gene. Members of the C/EBP family of transcription factors can also interact with elements of the proximal rat and mouse CCSP/UG promoters. The onset of C/EBP alpha expression in Clara cells correlates with the strong increase of CCSP/UG expression. Thus, C/EBP alpha may play a crucial role for differentiation-dependent CCSP/UG expression. Transfection studies demonstrate that C/EBP alpha and TTF-1 can synergistically activate the murine CCSP/UG promoter. Altogether, these results suggest that C/EBP alpha, TTF-1, and HNF-3 determine the Clara cell-specific, differentiation-dependent expression of the CCSP/UG gene in murine lung. The relative importance of these three transcription factors, however, differs in rabbits and humans.

Purification and characterization of the preprotein translocase of the outer mitochondrial membrane from Arabidopsis. Identification of multiple forms of TOM20

The translocase of the outer mitochondrial membrane (TOM) complex is a preprotein translocase that mediates transport of nuclear-encoded mitochondrial proteins across the outer mitochondrial membrane. Here we report the purification of this protein complex from Arabidopsis. On blue-native gels the Arabidopsis TOM complex runs at 230 kD and can be dissected into subunits of 34, 23, 21, 8, 7, and 6 kD. The identity of four subunits could be determined by immunoblotting and/or direct protein sequencing. The 21- and the 23-kD subunits exhibit significant sequence homology to the TOM20 preprotein receptor from other organisms. Analysis by two-dimensional isoelectric focusing/Tricine sodium dodecyl sulfide-polyacrylamide gel electrophoresis revealed the presence of further forms for Arabidopsis TOM20. All TOM20 proteins comprise a large cytoplasmically exposed hydrophilic domain, which is degraded upon trypsination of intact mitochondria. Clones encoding four different forms of Arabidopsis TOM20 were identified and sequenced. The deduced amino acid sequences are rather conserved in the N-terminal half and in the very C-terminal part, but include a highly variable glycine-rich region close to the C terminus. Implications on the function of plant TOM complexes are discussed. Based on peptide and nucleic acid sequence data, the primary structure for Arabidopsis TOM40 is presented.

Deep venous thrombosis and consecutive pulmonary embolism as the first sign of an ovarian cancer: MR angiography using an intravascular contrast agent (CLARISCAN)

We describe a case of progressive deep venous thrombosis and chest pain studied by contrast-enhanced magnetic resonance (MR) angiography with the new intravascular contrast medium CLARISCAN (NC100150 Injection). Combined MR venography and angiography demonstrated pelvic vein thrombosis and consecutive pulmonary embolism caused by a large abdominal tumor, diagnosed as an ovarian cancer after surgery. The potential role of an intravascular contrast medium for studying the vascular system in multiple regions of the body within a single examination without the need for bolus timing is discussed. J. Magn. Reson. Imaging 2000;12:497-500.

Distribution, targeting, and internalization of the sst4 somatostatin receptor in rat brain

Somatostatin mediates its diverse physiological effects through a family of five G-protein-coupled receptors (sst(1)-sst(5)); however, knowledge about the distribution of individual somatostatin receptor proteins in mammalian brain is incomplete. In the present study, we have examined the regional and subcellular distribution of the somatostatin receptor sst(4) in the rat CNS by raising anti-peptide antisera to the C-terminal tail of sst(4). The specificity of affinity-purified antibodies was demonstrated using immunofluorescent staining of HEK 293 cells stably transfected with an epitope-tagged sst(4) receptor. In Western blotting, the antiserum reacted specifically with a broad band in rat brain, which migrated at approximately 70 kDa before and approximately 50 kDa after enzymatic deglycosylation. sst(4)-Like immunoreactivity was most prominent in many forebrain regions, including the cerebral cortex, hippocampus, striatum, amygdala, and hypothalamus. Analysis at the electron microscopic level revealed that sst(4)-expressing neurons target this receptor preferentially to their somatodendritic domain. Like the sst(2A) receptor, sst(4)-immunoreactive dendrites were often closely apposed by somatostatin-14-containing fibers and terminals. However, unlike the sst(2A) receptor, sst(4) was not internalized in response to intracerebroventricular administration of somatostatin-14. After percussion trauma of the cortex, neuronal sst(4) receptors progressively declined at the sites of damage. This decline coincided with an induction of sst(4) expression in cells with a glial-like morphology. Together, this study provides the first description of the distribution of immunoreactive sst(4) receptor proteins in rat brain. We show that sst(4) is strictly somatodendritic and most likely functions in a postsynaptic manner. In addition, the sst(4) receptor may have a previously unappreciated function during the neuronal degeneration-regeneration process.

Lectin-binding pattern of primary malignant melanomas and melanocytic nevi

A panel of six biotinylated lectins was applied in order to study the composition and distribution of plasma membrane carbohydrate residues in 83 primary cutaneous melanomas (MMs) and in 85 melanocytic nevi (MN) with the avidin-biotin peroxidase technique. No clear-cut differences between MN and MMs were observed with regard to the staining with lectins. In MN and MMs derived from different patients, the lectin-binding pattern was variable and heterogeneous even within the individual nevi or melanomas. It seems reasonable, therefore, to assume that the lectin-binding pattern cannot be regarded as a reliable histochemical marker for the differentiation of MN from MMs. Moreover, because the pattern reveals no statistically significant correlation with the thickness or the depth of invasion of MM, it seems to lack prognostic significance.

[Serous peritoneal papillary tumor of low malignancy potential. Report of a case]

Papillary serous carcinoma with low malignant potential, similar to those described in the ovary, can also originate in the peritoneum. Characteristically they show peritoneal spread without involvement of the ovary and, if present, it corresponds to a superficial implant similar to those seen in the rest of the peritoneal cavity. Histologically they correspond to a low malignant potential tumor; they are slow growing and have good prognosis. They are common in young women, usually they present few symptoms and are frequently discovered during other surgical procedures. The treatment is surgical and it can be conservative in cases of women who want to preserve their fertility, without coadjuvant therapy. We report a 34 years old woman with a primary peritoneal serous carcinoma with low malignant potential and discuss its management.

Emittance growth during bunch compression in the CTF-II

Measurements of the beam emittance during bunch compression in the CLIC Test Facility (CTF-II) are described. The measurements were made with different beam charges and different energy correlations versus the bunch compressor settings which were varied from no compression through the point of full compression and to overcompression. Significant increases in the beam emittance were observed with the maximum emittance occurring near the point of full (maximal) compression. Finally, evaluation of possible emittance dilution mechanisms indicates that coherent synchrotron radiation was the most likely cause.

Comprehensive critical incident monitoring in a neonatal-pediatric intensive care unit: experience with the system approach

OBJECTIVE

To examine the occurrence of critical incidents (CIs) in order to improve quality of care.

DESIGN

Prospective survey.

SETTING

Multidisciplinary, neonatal-pediatric intensive care unit (ICU) of a non-university, teaching children's hospital.

PATIENTS

Four hundred and sixty-seven admissions over a 1-year period.

METHODS

A CI is any event which could have reduced, or did reduce, the safety margin for the patient. Comprehensive, anonymous, non-punitive CI monitoring was undertaken. CI severity with respect to actual patient harm was graded: major (score 3), moderate (2) or minor (1). The system approach incorporates the philosophy that errors are evidence of deficiencies in systems, not in people. We undertook 2-monthly analyses of CIs.

RESULTS

There were 211 CI reports: 30 % major, 25 % moderate, 45 % minor. The CI categories were management/environment 29 %, drugs 29 %, procedures 18 %, respiration 14 %, equipment dysfunction 7 %, nosocomial infections 3 %. The respiratory CIs were the most severe, the drug-related CIs the least severe (score mean, SD: 2.9, 0.26 vs 1.4, 0.76; p < 0.001). However, 20 out of 62 drug-related CIs were potentially life-threatening. Thirteen percent of drug CIs were decimal point errors. Eleven of the 29 respiratory CIs were accidental extubations (2.6/100 ventilator days). CIs were most often precipitated by consultants (32 %), followed by residents (23 %, over-represented in drug CIs, 22/62) and specialized nurses (21 %). Doctors had a greater proportion of major CIs than nurses (p < 0.01). Fifty percent of the CIs were detected by routine checks. The most important method of detection was patient inspection (44 %), alarms accounted for only 10 %. Contributing factors were human errors (63 %), communication failure (14 %), organizational problems (10 %), equipment dysfunction (7 %) and milieu (3 %).

CONCLUSIONS

CIs are very common in pediatric intensive care. Knowledge of them is a precious source for quality improvement through changes in the system.