Clinical evaluation of bone quality of particulate cancellous bone and marrow, and implant prosthetic rehabilitation.

This study aimed to subjectively evaluate bone quality in the particulate cancellous bone and marrow (PCBM) graft area and to assess the survival rates of implants. A retrospective review was conducted based on patient age, sex, diagnosis, reconstructed site, number of implants, prosthetic type, and duration of follow-up. Images from computed tomography (CT) before implant insertion were obtained and used in this study. We selected a 4.0-mm diameter × 8.0-mm length region of interest in the implant placement area, and measured the CT attenuation value. No significant correlations were seen between CT attenuation values and implant survival rates in the maxilla and mandible. On the other hand, CT attenuation values and implant survival rates were significantly lower in patients with malignancy than in non-malignant cases. Placing implants in PCBM grafted bone requires a full understanding of bone quality before surgery and drilling to ensure primary stability, along with consideration of soft tissue management and maintenance programs.

Salivary metabolites as potential predictive biomarkers for lung surgery complications: a retrospective cross-sectional study.

PURPOSE: Saliva is often used as a tool for identifying systemic diseases because of the noninvasive nature of its collection. Moreover, salivary metabolites can be potential predictive factors for postoperative survival. We conducted the present study to establish whether salivary metabolites can function as predictive biomarkers for lung surgery complications. METHODS: Unstimulated salivary samples were collected from 412 patients before lung surgery. Salivary metabolites were analyzed comprehensively by capillary electrophoresis mass spectrometry. Clinical data with the discriminatory ability of biomarkers were assessed to predict lung surgery complications using multivariate logistic regression analysis. The primary endpoint was the risk factors for postoperative complications of Clavien-Dindo grade ≥ III. RESULTS: Postoperative complications of Clavien-Dindo grade ≥ III developed in 36 patients (8.7%). There was no postoperative 30-day mortality. Male sex (odds ratio [OR], 3.852; 95% confidence interval CI 1.455-10.199; p = 0.007) and salivary gamma-butyrobetaine (OR, 0.809; 95% CI 0.694-0.943; p = 0.007) were identified as significant risk factors for postoperative complications of Clavien-Dindo grade ≥ III. CONCLUSION: Salivary metabolites are potential noninvasive biomarkers for predicting postoperative complications of lung surgery.

Factors influencing delayed referral of oral cancer patients from family dentists to the core hospital.

Background/purpose: Most oral cancer (OC) cases are identified by family dentists in Japan. However, a significant number of patients with OC in Japan are referred to core hospitals at advanced stages. Therefore, identifying the factors that contribute to delayed referrals from family dentists to core hospitals is crucial for detecting OC in its earlier stages. The aim of this retrospective study was to identify the risk factors for referral delays from family dentists to core hospitals. Materials and methods: The study included 63 patients with OC who were referred by family dentists to the Yamagata University Hospital between 2010 and 2022. The clinical parameters related to referral delays were retrospectively investigated using letters of reference provided by the family dentists and patient charts. Backward multiple regression analysis was performed to identify the relationships between the length of referral delay and potential risk factors. Additionally, backward multivariate logistic regression analysis was performed to examine the independent association between referral delays of >4 weeks and several clinical parameters. Results: Multiple regression analysis revealed that misdiagnosis of malignant lesions by family dentists (P = 0.047) was significantly associated with longer referral delays. Additionally, misdiagnosis of malignant lesions by family dentists was also an independent risk factor for referral delays of >4 weeks (odds ratio, 10.387; P = 0.006). Conclusion: Misdiagnosis of malignant lesions by family dentists was a significant risk factor for referral delays from family dentists to core hospitals. Our results will motivate family dentists to improve their ability to diagnose OC.

Associations between subjective well-being, number of teeth, and self-rated mastication in Japanese adults: A cross-sectional study.

This cross-sectional study aimed to investigate the risk factors for low levels of subjective well-being (SWB) in the general population of Japan, specifically, the impact of the number of teeth and self-rated mastication. The surveyed population consisted of individuals aged between 40 and 79 years from Yamagata prefecture, Japan. A postal self-administered questionnaire survey of respondents lifestyles, medical history, oral health, and dietary intake, was conducted from 2017 to 2021. We included 6846 participants to confirm the independent associations between SWB and several parameters using multivariate ordinal logistic regression analysis to estimate adjusted odds ratios and 95% confidence intervals. Individuals with < 20 teeth and poor mastication ability had a 1.3-fold risk for low levels of SWB compared with individuals with ≥ 20 teeth with good mastication ability (adjusted odds ratios = 1.300, 95% confidence intervals = 1.043-1.621, P = .020). There were no differences between individuals with good mastication ability, regardless of the number of remaining teeth. Our study emphasizes not only the importance of having ≥ 20 teeth and good mastication ability for high levels of SWB but also the importance of restoring mastication ability using some form of prosthesis, to facilitate a high level of SWB when the number of remaining teeth is < 20.

Measures of oral health-related quality of life in patients with bone graft and implant prosthetic rehabilitation at the anterior of mandible/maxilla among young and middle-aged adults: a retrospective pilot study.

OBJECTIVES: Dental implants are believed to contribute to improved masticatory function and oral health-related quality of life (OHRQOL), but the details remain unclear. The aim of this study was to evaluate the clinical outcomes of dental implant prosthetic rehabilitation after bone graft at the anterior mandible/maxilla based on OHRQOL, particularly in young and middle-aged patients. METHODS: This retrospective study included 11 patients who received bone grafts at the anterior mandible/maxilla and dental implant surgery. Chewing function score and OHRQOL (using the Oral Health Impact Profile-14 questionnaire) were evaluated before and after completion of an implant-retained bridge or removable implant-supported denture. RESULTS: Chewing function score tended to improve slightly after dental implant prosthetic rehabilitation, but none of the observed differences were significant. In the assessment of OHRQOL, relatively worse domain scores before completion of dental implant prosthetic rehabilitation were seen for Functional limitation, Psychological discomfort, and Psychological disability. Conversely, Social disability seemed relatively unaffected by tooth loss. All domain scores and total scores for items other than Physical disability and Social disability were significantly improved after completion of dental implant rehabilitation. CONCLUSIONS: Tooth loss in the anterior region may not significantly affect chewing function score, but can have a significant impact on OHRQOL. Bone grafts and dental implant prosthetic rehabilitation can resolve these problems, and the results of this study will benefit both patients and medical professionals in terms of treatment planning and informed consent.

Association of health behaviors, dietary habits, and oral health with weight gain after 20 years of age in community-dwelling Japanese individuals aged 40 years and older: a cross-sectional study.

OBJECTIVES: This cross-sectional study investigated the factors associated with weight gain ≥ 10 kg after 20 years of age in the general Japanese population, with a focus on the number of teeth. MATERIALS AND METHODS: We included individuals aged ≥ 40 years from Yamagata prefecture, Japan from 2017-2021. A postal survey was conducted using a self-administered questionnaire; 5,940 participants were included in the final analysis. The questionnaire included items on lifestyle factors, medical history, physical and mental conditions, oral health, and dietary intake. A multivariate logistic regression analysis was used to identify independent associations between weight gain ≥ 10 kg after 20 years of age and various parameters; adjusted odds ratios (ORs) and 95% confidence intervals (CIs) were estimated. RESULTS: Less than 20 teeth, male sex, drinking habit frequency, eating very fast or fast, and a higher frequency of eating-away-from-home were significant factors associated with weight gain ≥ 10 kg after 20 years of age; individuals with < 20 versus > 20 teeth exhibited a 1.35-fold higher OR (95% CI 1.15-1.59; p < 0.01). CONCLUSIONS: Our results suggest that having < 20 teeth may affect weight gain ≥ 10 kg after 20 years of age. However, owing to the cross-sectional study design, causality could not be determined. Therefore, maintaining healthy lifestyle behaviors to avoid tooth loss may also affect weight gain ≥ 10 kg after 20 years of age. CLINICAL RELEVANCE: Having < 20 teeth has the potential to affect long-term weight gain after 20 years of age.

Salivary metabolomics for oral leukoplakia with and without dysplasia.

PURPOSE: Oral leukoplakia (OL) is a common potentially malignant oral disorder. Therefore, there is a need for simple screening methods for OL before its transformation into oral cancer. Furthermore, because invasive open biopsy is the sole method to determine if an OL lesion is dysplastic, there is also a clinical need for non-invasive methods to differentiate dysplastic OL from non-dysplastic OL. This study aimed to identify salivary metabolites that can help differentiate patients with OL from healthy controls (HC) and also dysplastic OL from non-dysplastic OL. MATERIAL & METHODS: Whole unstimulated saliva samples were collected from patients with OL (n = 30) and HCs (n = 29). The OL group included nine patients with dysplastic OL and 20 with non-dysplastic OL. Hydrophilic metabolites in the saliva samples were comprehensively analyzed through capillary electrophoresis mass spectrometry. To evaluate the discrimination ability of a combination of multiple markers, a multiple logistic regression (MLR) model was developed to differentiate patients with OL from HCs and dysplastic OL from non-dysplastic OL. RESULTS: Twenty-eight metabolites were evidently different between patients with OL and HCs. Finally, three metabolites (guanine, carnitine, and N-acetylputrescine) were selected to develop the MLR model, which resulted in a high area under curve (AUC) of the receiver operating characteristic (ROC) to differentiate patients with OL from HCs (AUC = 0.946, p < 0.001, 95% confidential interval [CI] = 0.889- 1.000). Similarly, two metabolites were evidently different between patients with dysplastic and non-dysplastic OL. Finally, only one metabolite (7-methylguanine) was selected in the MLR model, which revealed a moderate discrimination ability for dysplastic and non-dysplastic OL (AUC = 0761, p = 0.027, 95% CI = 0.551-0.972). CONCLUSION: Our candidate salivary metabolites showed potential not only to discriminate OL from HC, but also to discriminate dysplastic OL from non-dysplastic OL.

Evaluation of radiographic characteristics and surgical removal of 147 mesiodens.

The aim of this study was to evaluate the radiographic characteristics and surgical removal of mesiodens among patients who had attended the Department of Dentistry, Oral and Maxillofacial-Plastic and Reconstructive Surgery of the Faculty of Medicine, Yamagata University. This study included 121 patients in the final analysis. We retrospectively reviewed medical records including patient age, sex, mesiodens number, direction, position, opportunity for detection, surgical approach and operating time. The 121 patients comprised 82 males and 39 females. Mean age was 7.6 ± 3.1 years (range, 4-35 years). The total number of mesiodens among these 121 patients was 147. Ninety-six patients had one mesiodens, 24 patients had two mesiodens and 1 patient had 3 mesiodens. Seventy-nine mesiodens were detected while taking X-rays for routine dental examination and/or orthodontic treatment at their family dental/orthodontic clinic. Mean operating time for removal of the 147 mesiodens was 32.2 ± 18.1 min. Among the 96 patients with one mesiodens, mean operating time for removal of the mesiodens was 30.7 ± 16.5 min. Operating time for removal of a mesiodens tended to be prolonged with increased distance from the alveolar crest. Early detection of mesiodens on routine radiographic check-ups and surgical planning considering patient age, crown direction, position of the mesiodens will contribute to improved treatment of mesiodens.

Association of the number of teeth and self-rated mastication with self-rated health in community-dwelling Japanese aged 40 years and older: the Yamagata cohort study.

Self-rated health (SRH) is a predictive factor for health-related prognoses such as mortality. This study aimed to comprehensively investigate the risk factors for poor SRH in the general population of Japan, focusing on the combination of the number of teeth and self-rated mastication. Individuals aged at least 40 years in Yamagata Prefecture, Japan, were surveyed from 2017 to 2021. The participants answered a self-administered postal survey on lifestyle factors, medical history, physical and mental conditions, oral health, and dietary intake, and 6739 participants were included. Multivariate logistic regression analysis showed that individuals with less than 20 teeth and who bite tightly on one side or neither side were at a 1.422- and 1.952-fold significantly higher risk, respectively, of poor SRH than individuals with at least 20 teeth and who bite tightly on both sides. Moreover, individuals who had less than 20 teeth but could bite tightly on both sides did not have a significant risk compared to those who had at least 20 teeth and could bite tightly on both sides. Regarding individuals with more than 20 teeth, there was no difference between those who could and could not bite tightly on both sides, although the odds ratios for poor SRH tended to increase for those who could bite on one side or neither side. Our results emphasize the importance of having at least 20 teeth without periodontal disease and oral rehabilitation using a type of prosthesis for SRH, even with less than 20 teeth.

Association between the duration of antibiotic prophylaxis and surgical site infection after orthognathic surgery in Japan.

PURPOSE: This study aimed to evaluate the risk factors for surgical site infection (SSI) after orthognathic surgery, focusing on the duration of prophylactic antibiotic administration in Japan. STUDY DESIGN: The study included 181 patients who underwent orthognathic surgery at the Department of Oral and Maxillofacial Surgery of Yamagata University Hospital between 2012 and 2021. The clinical parameters of SSI were retrospectively investigated using patient charts. Logistic regression analysis was used to estimate the odds ratios (ORs) with 95% confidence intervals (CIs) for risk factors for SSI after orthognathic surgery. RESULTS: Nineteen patients (10.5%) were complicated with SSI. Male sex (OR, 3.638; 95% CI, 1.316-10.058) and an antibiotic prophylaxis duration ≤3 days (OR, 12.718; 95% CI, 1.639-98.673) were independent risk factors for SSI after orthognathic surgery. CONCLUSION: Extended-term antibiotic prophylaxis was more effective for prevention of SSI after orthognathic surgery than short-term in this study.

A Cross-Sectional Survey on the Association between Dental Health Conditions and University Personality Inventory Scores among University Students: A Single-Center Study in Japan.

This study examined the association between dental health conditions and scores on the University Personality Inventory (UPI) among university students in Japan. Participants were freshmen at Yamagata University between 2010 and 2019. Dental check-ups, including dental caries, periodontal disease, malocclusion, and temporomandibular disorders (TMD), and mental health screening using the UPI were performed; 12,433 students were included in the final analysis. A logistic regression analysis was performed to confirm the association between dental health conditions and >30 UPI scores, which indicate the need to consult mental health professionals. Overall, students who required treatment for TMD had a 3.165-fold higher risk of >30 UPI scores (OR = 3.165, 95% CI = 1.710−5.857). Periodontal disease and TMD in male participants (periodontal disease: OR = 1.329, 95% CI = 1.108−1.595; TMD: OR = 3.014, 95% CI = 1.107−8.204) and TMD in female participants (OR = 2.938, 95% CI = 1.340−6.445) were significant risk factors for >30 UPI scores. Students requiring treatment for TMD were at risk of obtaining >30 UPI scores. Although our study has several limitations, students with subjective symptoms (e.g., disturbance in opening the mouth) should take the UPI test or in some cases consult mental health professionals.

Salivary Metabolomics for Prognosis of Oral Squamous Cell Carcinoma.

This study aimed to identify salivary metabolomic biomarkers for predicting the prognosis of oral squamous cell carcinoma (OSCC) based on comprehensive metabolomic analyses. Quantified metabolomics data of unstimulated saliva samples collected from patients with OSCC (n = 72) were randomly divided into the training (n = 35) and validation groups (n = 37). The training data were used to develop a Cox proportional hazards regression model for identifying significant metabolites as prognostic factors for overall survival (OS) and disease-free survival. Moreover, the validation group was used to develop another Cox proportional hazards regression model using the previously identified metabolites. There were no significant between-group differences in the participants' characteristics, including age, sex, and the median follow-up periods (55 months [range: 3-100] vs. 43 months [range: 0-97]). The concentrations of 5-hydroxylysine (p = 0.009) and 3-methylhistidine (p = 0.012) were identified as significant prognostic factors for OS in the training group. Among them, the concentration of 3-methylhistidine was a significant prognostic factor for OS in the validation group (p = 0.048). Our findings revealed that salivary 3-methylhistidine is a prognostic factor for OS in patients with OSCC.

Characterization of the interaction between Trypanosoma brucei Pex5p and its receptor Pex14p.

The interaction of Trypanosoma brucei (Tb) Pex5p and its receptor TbPex14p is essential for the translocation of newly synthesized matrix proteins into the glycosome. Here, we reveal that only the third WXXXF/Y motif of TbPex5p is involved in the interaction and that negative charge of the fourth amino acid is important. We suggest that Phe35 and Phe52 of TbPex14p interact with Trp318 and Phe322 in the third motif and that the Lys56 adjacent to Phe35/Phe52 associates with the fourth Glu in the motif to make the complex. This information is expected to be useful for developing anti-trypanosomal drugs.

Risk of subsequent biliary malignancy in patients undergoing cyst excision for congenital choledochal cysts.

BACKGROUND AND AIM: The aim of this study was to elucidate the risk of subsequent biliary malignancy in patients undergoing cyst excision for congenital choledochal cysts. METHODS: A retrospective analysis of 94 patients who had undergone cyst excision for congenital choledochal cysts was conducted. The median age at the time of cyst excision and median follow-up time after cyst excision were 7 years and 181 months, respectively. RESULTS: Biliary tract cancer developed in four patients at 13, 15, 23, and 32 years after cyst excision. The cumulative incidences of biliary tract cancer at 15, 20, and 25 years after cyst excision were 1.6%, 3.9%, and 11.3%, respectively. The sites of biliary tract cancer were the intrahepatic (n = 2), hilar (n = 1), and intrapancreatic (n = 1) bile ducts. Of the four patients with biliary tract cancer after cyst excision, three patients underwent surgical resection and one patient received chemo-radiotherapy. The overall cumulative survival rates after treatment in the four patients with biliary tract cancer were 50% at 2 years and 25% at 3 years, with a median survival time of 15 months. CONCLUSIONS: The risk of subsequent biliary malignancy in patients undergoing cyst excision for congenital choledochal cysts seems to be relatively high in the long-term. The risk of biliary malignancy in the remnant bile duct increases more than 15 years after cyst excision. Despite an aggressive treatment approach for this condition, subsequent biliary malignancy following cyst excision for congenital choledochal cysts shows an unfavorable outcome.

Tracheoplasty using a metallic fusiform centrally-doubled coiled stent for a major tracheal defect in rabbits.

BACKGROUND/PURPOSE: The long-term survival rate of rabbits treated with a fusiform metallic coil for a large tracheal wall defect is 60%. In the present study, the central half of a simple coil was covered by a double coil to prevent the ingrowth of the surrounding connective tissue and to provide a sutureless fixation of the coil to obtain a further increase in the survival rate. STUDY DESIGN: The anterior half of the tracheal wall was removed for a longitudinal length of 6 tracheal rings to make a large tracheal defect. Metallic coils were placed into the tracheal lumen through the wall defect. The doubly-coiled portion was designed to fit the length of the defect to eliminate the need for suture fixation. The survival at two months after the operation, endoscopic findings and histological changes were evaluated. RESULTS: All 6 rabbits treated with a centrally-doubled coiled stent survived without major respiratory trouble for at least 2 months. Endoscopic examinations performed 1 month after the operation revealed an irregular coating of reddish granulation tissue inside the coil, and a wet portion was aspirated. The tracheal defect was replaced with fibrous tissue, but neither a complete epithelialization nor cartilage formation was observed. CONCLUSION: These results suggest that the metallic coil was useful to obtain an improvement in the survival of rabbits with a large tracheal wall defect. Therefore, this new coil might be indicated for the treatment of tracheal wall defects.

Effects of neuromodulation with sacral magnetic stimulation for intractable bowel or bladder dysfunction in postoperative patients with anorectal malformation: a preliminary report.

BACKGROUND AND PURPOSE: The effects of neuromodulation with sacral magnetic stimulation (SMS) were examined in postoperative patients with bowel or bladder dysfunction. PATIENTS AND METHODS: SMS was performed at the S3 level using a MagPro® instrument (Medtronic Inc., USA) while the patients were under light sedation. One treatment course consisted of stimulation delivered at 15 Hz for 5 s, 10 times over an interval of 1 min. Three patients with bladder or bowel dysfunction refractory to conservative treatment were examined. RESULTS: Case 1 is a 7-year-old male with a rectourethral fistula. This patient developed a hyperdynamic bladder after a laparoscopic pull-through operation at the age of 7 months. The administration of an anticholinergic agent slightly improved the condition. SMS was started at the age of 4 years with one trial each year. A marked expansion of bladder volume from 20 ml before trial to 120 ml after the third trial was obtained. Case 2 (a 4-year old female with a recto-vaginal fistula) and Case 3 (a 8-year-old female with an ano-vestibular fistula) showed severe constipation after radical surgery during infancy. Case 2 needed appendicostomy. After SMS, bowel movements could become controllable with enemas. No adverse effects were observed for any of the three cases. CONCLUSIONS: These results suggest that SMS might be a useful modality to improve postoperative bowel or bladder dysfunction.

Usefulness of bFGF spray in the treatment of perianal abscess and fistula-in-ano.

PURPOSE: Basic fibroblast growth factor (bFGF) is a newly identified recombinant agent that promotes wound healing through an augmented neovascularization. This study examined the effect of bFGF in the treatment of perianal abscesses. PATIENTS AND METHODS: Nine consecutive males with an average age of 5.1 months (1-9 months) who presented with perianal abscess in the past 2 years were treated with bFGF (Transfermin, Kaken Co., Ltd., Tokyo, Japan). Two or three sprays of bFGF were applied to the perianal abscess two times a day. RESULTS: All nine patients responded well to the bFGF treatment. Pus discharge and local swelling around the fistula subsided within a mean of 7.3 ± 1.9 days (1 SD) after the initiation of treatment. One case showed a mild relapse 7 months after treatment and the other developed a new lesion 1 month after treatment. However, these lesions also similarly disappeared after a second treatment with bFGF without a recurrence in the follow-up examinations at 11 and 10 months, respectively. The remaining seven cases have all done well without any recurrence at a mean follow-up period of 14.1 ± 3.2 months. CONCLUSION: These results clearly indicate the usefulness of the bFGF spray as a new treatment strategy for the management of perianal abscesses.

Mortality and morbidity of patients with neuroblastoma who survived for more than 10 years after treatment--Niigata Tumor Board Study.

PURPOSE: To evaluate the utility of treatment strategies in neuroblastoma (NB), the survival of the NB patients was retrospectively examined. METHODS: During the past 40 years from 1967 to 2006, 103 NB patients not detected by the mass screening program were treated. The patients were divided into 3 groups; the period of aggressive surgery (AS group: 43 patients) from 1967 to 1984, the period of aggressive chemotherapy (AC group: 40 patients), from 1985 to 1996, and the period of mega-chemotherapy with stem cell transplantation since 1997. The patients treated in the AC and the AS groups were examined. RESULTS: The survival curve reached a nadir within 3 years in the AS group, whereas the second major drop of the survival curve was found in the AC group, which was owing to late mortality of 7 patients more than 10 years after the initiation of treatment. As a result, the overall survival in the AS and the AC groups were approximately 30.2% and 30.0% at 20 years after treatment, respectively. A different kind of strategy-related morbidity was found in 46% of EFS in both the AS and the AC groups. CONCLUSIONS: The effectiveness of a treatment strategy should therefore be assessed after several decades.

Removal of a hydrogenated amorphous carbon film from the tip of a micropipette electrode using direct current corona discharge.

Micropipette electrodes are fabricated by coating glass micropipettes first with metal and then with hydrogenated amorphous carbon (a-C:H) as an electrical insulator. Furthermore, at the tip of the micropipette electrode, the deposited a-C:H film needs to be removed to expose the metal-coated surface and hollow for the purposes of electrical measurement and injection. This paper describes a convenient and reliable method for removing the a-C:H film using direct current corona discharge in atmospheric air. The initial film removal occurred at an applied voltage of 1.5-2.0 kV, accompanied by an abrupt increase in the discharge current. The discharge current then became stable at a microampere level in the glow corona mode, and the removed area gradually extended.

A 2-year-old boy with a stage III yolk sac tumor occurring in an intra-abdominal retained testis.

A major complication of retained testes is an occurrence of malignancy later in life. We, herein, report the case of a 2-year-old boy who presented with a huge yolk sac tumor with retroperitoneal lymph nodes metastasis that originated in a left intra-abdominal undescended testis. Computed tomography and magnetic resonance imaging showed a huge round tumor connecting to the left retroperitoneal lymph nodes with metastasis extending from the left pelvic region to the left renal hilum. The serum alpha-fetoprotein level was 36,528 ng/mL. The right abdominal tumor appeared to be a giant testis that had strangulated at the neck of the cord. The tumor had ruptured at the side of the left pelvic lymph node metastasis, and a yolk sac tumor was diagnosed from a histologic analysis of the resected specimens. Postoperative PEB chemotherapy was effective, and a complete surgical resection of the tumor was performed 3 months after the initial laparotomy. The pathologic findings showed fibrous tissue without any tumor cells. The patient has been doing well for 18 months after the radical operation. This case might be a coincidental association of a yolk sac tumor occurring in an undescended testis, which thus caused a delay in making an accurate diagnosis.