Tolerating spelling errors during patient validation

Misspellings, typographical errors, and variant name forms present a considerable problem for a Clinical Information System when validating patient data. Algorithms to correct these types of errors are being used, but they are based either on a study of frequent types of errors associated with general words in an English text rather than types of errors associated with the spelling of names, or on errors that are phonologically based. This paper investigates the types of errors that are specifically associated with the spelling of patient names, and proposes an algorithm that effectively handles such types of errors. This paper also studies the effectiveness of several relaxation techniques and compares them with the one that is being proposed.

Testing spatial understanding of anatomy

A system was designed to test the medical student's ability to recognize and locate anatomical cross-sections. The computer was used to prepare the data, present the test and track the user's responses. The nature of the test was such that it could be prepared, presented and used much more easily on the computer than on paper. The system was used successfully by anatomists and medical students.

Effects of low-dose cimetidine on nocturnal acid secretion in healthy subjects

The effects of 100 mg and 200 mg bedtime doses of cimetidine on nocturnal gastric acid secretion were examined in nine healthy subjects in a double blind, placebo controlled, randomised three way crossover study. Treatment was given at 23.00 hours and the gastric contents continually aspirated from midnight until 07.00 hours the following morning. Hourly aliquots were analysed for pH and acid output. Relative to placebo the 100 mg and 200 mg doses of cimetidine respectively increased mean pH by 2.22 and 2.63 units/h (P less than 0.001) with mean acid output decreasing by 0.95 and 0.98 mmol/h (P less than 0.001). Whilst mean pH was higher and mean acid output was lower for 200 mg cimetidine compared to 100 mg cimetidine the difference was not statistically significant. Mean hourly pH was consistently above pH 3 for 100% of the time for both doses of cimetidine whereas mean pH failed to reach this value at anytime on placebo. Low doses of cimetidine taken at bedtime effectively reduced nocturnal gastric acid secretion in healthy individuals.

Mediastinitis following coronary artery bypass surgery: a 3-year review

Twenty cases of mediastinitis after coronary artery bypass graft operations in 1985-1987 were reviewed to determine risk factors. Two distinct clusters with a methicillin-resistant Staphylococcus aureus (MRSA) strain occurred in 1986. One resident was exposed to six cases but to only 5 of 24 controls (P less than .008). Cultures of his nares in January and November 1986 revealed the same MRSA strain as that of the cases. An attempt to eradicate the resident's nasal carriage of MRSA in January 1986 failed; eradication of his carrier state was achieved only after treatment with mupirocin. In a case-control study examining patients exposed to the resident, a prolonged duration of surgery (P less than .05) and a preoperative albumin level of less than 3.0 g/dl (P less than .009) were associated with mediastinitis with this MRSA. For the other 14 mediastinitis patients, who were not exposed to the resident, a preoperative albumin level of less than 3.0 g/dl was also a risk factor (8/14 cases vs. 8/43 controls, P less than .009). Thus, this study suggests that it is important to follow MRSA disseminators and to recognize that preoperative serum albumin levels are a risk factor for mediastinitis.

Conceptual data model for a central patient database

This paper presents methods used to develop a conceptual model for a patient database forming the centerpiece of a clinical information system under development. Various modeling techniques are discussed using a simplified fragment of the model. A method for mapping the model onto a relational design optimized for single patient retrievals is described. The results section discusses a number of issues pertaining to the flexibility and usability of this architecture.

Validating patient names in an integrated clinical information system

Methods for validating patient names during the upload of clinical records are described. Exact string matching, Soundex method and a pattern matching algorithm (LCS method) are described and compared to a manual analysis of 10000 patient name pairs. In addition, the types of spelling and typographical errors that occur in patient names in the pathology database at CPMC are described. The data analysis shows that the LCS method performs better than the other techniques when compared to manual analysis.

Intraoperative radiation of canine carotid artery, internal jugular vein, and vagus nerve. Therapeutic applications in the management of advanced head and neck cancers

As a step in the application of intraoperative radiotherapy (IORT) for treating advanced head and neck cancers, preliminary information was obtained on the radiation tolerance of the canine common carotid artery, internal jugular vein, and vagus nerve to a single, high-dose electron beam. Both sides of the neck of eight mongrel dogs were operated on to expose an 8-cm segment of common carotid artery, internal jugular vein, and vagus nerve. One side of the neck was irradiated, using escalating doses of 2500, 3500, 4500, and 5500 cGy. The contralateral side of the neck served as the unirradiated control. At 3 and 6 months after IORT, one dog at each dose level was killed. None of the dogs developed carotid bleeding at any time after IORT. Light microscopic investigations using hematoxylin-eosin staining on the common carotid artery and internal jugular vein showed no consistent changes that suggested radiation damage; however, the Masson trichrome stain and hydroxyproline concentration of irradiated common carotid artery indicated an increase in the collagen content of the tunica media. Marked changes in the irradiated vagus nerve were seen, indicating severe demyelination and loss of nerve fibers, which appeared to be radiation-dose dependent. Four patients with advanced recurrent head and neck cancer were treated with surgical resection and IORT without any acute or subacute complications. The role of IORT as a supplement to surgery, external beam irradiation, and chemotherapy in selected patients with advanced head and neck cancer needs further exploration.

Hemodialysis-associated febrile episodes: surveillance before and after major alteration in the water treatment system

Surveillance for bacteremic or pyrogenic episodes associated with hemodialysis was undertaken before and after the reconstruction of the water treatment system at our University medical center. The new water system included a holding tank with iodination treatment. The water delivered to individual dialysis stations had only occasional positive bacterial cultures (3 of 21 samples before completion of construction, 2 of 16 samples afterwards) and intermittent detection of endotoxin (6 of 21 samples before completion of construction, 9 of 16 samples afterwards) at monthly sampling. Among 51 individual dialysis treatments (25 patients) before reconstruction and 56 treatments (29 patients), after, only 2 and 3 febrile events were identified, respectively. All of these were associated with underlying infectious illness and not with the hemodialysis procedure itself. Overall, we conclude that pyrogenic episodes associated directly with hemodialysis treatment are infrequent, and that the addition of a water storage tank with iodination treatment does not appear to increase the risk of bacteremia or pyrogenic episodes.

An outbreak of Mycobacterium terrae in clinical specimens associated with a hospital potable water supply

We investigated an increase in the number of patient specimens yielding Mycobacterium terrae in 1986, isolation of M. terrae was associated with specimens obtained from inpatients at our new hospital, but not with specimens referred from other hospitals [37(+)/144 inpatient specimens versus 2(+)/26 referred specimens, p less than 0.05]. By October 31, 1987, we had identified 163 positive specimens from 131 patients. All M. terrae were isolated from specimens obtained from non-sterile sites, i.e., respiratory, gastrointestinal, or urine. No clinical disease related to M. terrae occurred. Review of procedures and cultures of solutions used in the Microbiology Laboratory suggested the source of M. terrae was not in the Microbiology Laboratory. An analysis of case location showed an association with hospital tier (p less than 0.05), a pattern matching the design of the potable water system of the hospital. M. terrae was cultured from multiple outlets of this system. There appeared to be multiple modes of transmission of M. terrae from this reservoir. Control measures included avoidance of water sources during specimen collection and hyperchlorination of the potable water system. These measures appeared to result in the disappearance of M. terrae from subsequent clinical specimens. We believe this to be the first report defining the epidemiologic aspects of M. terrae contaminating clinical specimens.

Treatment of hidradenitis suppurativa with combination hypothalamic-pituitary-ovarian and adrenal suppression. A case report

A 33-year-old woman with severe familial hidradenitis suppurativa of the vulva and perineum was treated with a combination of dexamethasone and a new synthetic gonadotropin releasing hormone agonist, leuprolide acetate. The clinical improvement paralleled the adrenal and ovarian suppression, as demonstrated by falling blood levels of testosterone, dehydroepiandrosterone sulfate, androstenedione and estradiol.

Oblique osteotomy of the fifth metatarsal: a five year review

A 5-year retrospective review of a nonfixated oblique osteotomy of the fifth metatarsal for repair of tailor's bunion was performed at the Podiatry Hospital of Pittsburgh. Subjective and objective analysis of 38 osteotomies were evaluated in 22 patients. Incidence of complications, transfer of lesions, and recurrence of the deformity were determined. Preoperative and 5-year postoperative radiographs were analyzed as to the effectiveness of this procedure in changing the intermetatarsal angle, lateral deviation angle, and the sagittal plane elevation of the fifth metatarsal head. While patient acceptance is high, the authors derive new conclusions regarding the overall effectiveness of this common podiatric procedure.

A measles outbreak at university medical settings involving health care providers

In 1985, a measles outbreak involved 14 students and non-student contacts in Michigan. Eight transmissions occurred at university medical facilities; five of these were likely airborne transmissions. Medical students and a medical resident were involved in the outbreak's propagation. Health care providers need to be immune to measles. Measles should be suspected in young adults with compatible illnesses; persons suspected to have measles should be placed in stringent respiratory isolation to preclude airborne transmission.

In vitro fertilization and embryo transfer in patients with one ovary

The purpose of this investigation was to compare follicular response and pregnancy rates in patients with one and two ovaries who have undergone in vitro fertilization (IVF). No statistically significant difference was found in serum estradiol levels on the day of human chorionic gonadotropin administration, mean number of follicles (greater than 15 mm), mean total number of oocytes recovered, mean number of mature oocytes recovered, or number of pregnancies per transfer. The total number of oocytes recovered in the one- and two-ovary groups was 47 and 123, respectively. There was a significantly greater mean number of immature oocytes recovered (1.5 +/- .03 versus 0.5 +/- 0.2, P less than 0.01) and embryos transferred (2.7 +/- 0.3 versus 1.7 +/- 0.3, P less than .04) in patients with two ovaries. Though not statistically significant, a trend was noted in the two-ovary group for a greater number of pregnancies per transfer (9:25 versus 2:14). The authors conclude that single-ovary patients may have a reduced outcome with IVF compared with patients with two ovaries.

Molecular detection of a translocation (Y;15) in a 45,X male

A 45,X male individual was shown to have a translocation of Y-chromosome material to the short arm or proximal long arm of chromosome 15. This translocation was detected by genomic DNA blotting and in situ hybridization with Y-chromosome-specific DNA probes.

Small deletions of the short arm of the Y chromosome in 46,XY females

Structural anomalies of the sex chromosomes provide a means to study the location of genes responsible for sex determination. Recently, a type of sex reversal in humans, the 46,XX male, was shown to result in some cases from translocation of Y chromosome material to the X chromosome. In the present report, another type of sex reversal, the 46,XY female, is shown to result, in two cases, from small deletions of the short arm of the Y chromosome. Prometaphase chromosome analysis showed a 46,X,Yp- karyotype. Several Y chromosome-specific DNA probes were found to be deleted in the two female patients. DNA analysis showed that the two deletions were different but included a common overlapping region likely to be essential for male determination.

Quantitative analysis of sex-chromosome mosaicism with X-Y DNA probes

Sex-chromosome mosaicism was quantitatively analyzed in two patients using DNA probes specific for human X and Y chromosomes. Both patients were female with stigmata of the Turner syndrome, and both had a 45,X cell line and a 46,XY cell line. One of the patients had a morphologically abnormal, nonfluorescent Y chromosome, dic(Y)(q11). Hybridization of DNA from this patient with two repetitive DNA sequences specific for the heterochromatic region of the Y chromosome indicated that most of the Y-heterochromatic sequences were deleted. DNA from both patients was hybridized with a probe for the DXYS1 locus and found to have the X- and Y-linked loci. Densitometric measurements of the relative intensities of the X- and Y-linked bands were used to calculate the degree of mosaicism in each case. The percentages of 45,X cells obtained by DNA analysis agreed with those obtained by chromosome analysis. DNA analysis provides a way to quantitate mosaicism at the DNA level and in nondividing tissue.