SAGES guideline for the diagnosis and treatment of appendicitis

BACKGROUND

Appendicitis is an extremely common disease with a variety of medical and surgical treatment approaches. A multidisciplinary expert panel was convened to develop evidence-based recommendations to support clinicians and patients in decisions regarding the diagnosis and treatment of appendicitis.

METHODS

A systematic review was conducted from 2010 to 2022 to answer 8 key questions relating to the diagnosis of appendicitis, operative or nonoperative management, and specific technical and post-operative issues for appendectomy. The results of this systematic review were then presented to a panel of adult and pediatric surgeons. Evidence-based recommendations were formulated using the GRADE methodology by subject experts.

RESULTS

Conditional recommendations were made in favor of uncomplicated and complicated appendicitis being managed operatively, either delayed (>12h) or immediate operation (<12h), either suction and lavage or suction alone, no routine drain placement, treatment with short-term antibiotics postoperatively for complicated appendicitis, and complicated appendicitis previously treated nonoperatively undergoing interval appendectomy. A conditional recommendation signals that the benefits of adhering to a recommendation probably outweigh the harms although it does also indicate uncertainty.

CONCLUSIONS

These recommendations should provide guidance with regard to current controversies in appendicitis. The panel also highlighted future research opportunities where the evidence base can be strengthened.

Diagnosis and treatment of appendicitis: systematic review and meta-analysis

BACKGROUND

The optimal diagnosis and treatment of appendicitis remains controversial. This systematic review details the evidence and current best practices for the evaluation and management of uncomplicated and complicated appendicitis in adults and children.

METHODS

Eight questions regarding the diagnosis and management of appendicitis were formulated. PubMed, Embase, CINAHL, Cochrane and clinicaltrials.gov/NLM were queried for articles published from 2010 to 2022 with key words related to at least one question. Randomized and non-randomized studies were included. Two reviewers screened each publication for eligibility and then extracted data from eligible studies. Random effects meta-analyses were performed on all quantitative data. The quality of randomized and non-randomized studies was assessed using the Cochrane Risk of Bias 2.0 or Newcastle Ottawa Scale, respectively.

RESULTS

2792 studies were screened and 261 were included. Most had a high risk of bias. Computerized tomography scan yielded the highest sensitivity (> 80%) and specificity (> 93%) in the adult population, although high variability existed. In adults with uncomplicated appendicitis, non-operative management resulted in higher odds of readmission (OR 6.10) and need for operation (OR 20.09), but less time to return to work/school (SMD - 1.78). In pediatric patients with uncomplicated appendicitis, non-operative management also resulted in higher odds of need for operation (OR 38.31). In adult patients with complicated appendicitis, there were higher odds of need for operation following antibiotic treatment only (OR 29.00), while pediatric patients had higher odds of abscess formation (OR 2.23). In pediatric patients undergoing appendectomy for complicated appendicitis, higher risk of reoperation at any time point was observed in patients who had drains placed at the time of operation (RR 2.04).

CONCLUSIONS

This review demonstrates the diagnosis and treatment of appendicitis remains nuanced. A personalized approach and appropriate patient selection remain key to treatment success. Further research on controversies in treatment would be useful for optimal management.

Complex Surgical Management of Radiation-Associated Left Retroperitoneal Sarcoma

Radiation-associated sarcomas (RASs) are rare entities that tend to have an aggressive course and poor prognosis. Criteria for diagnosis of radiation-associated sarcoma include therapeutic radiation preceding the development of sarcoma, sarcoma arising within or near the irradiated field, and tumor histology that is distinct from the primary tumor necessitating radiation. Despite their relatively uncommon occurrence, RASs are a well-established complication of radiation therapy. We present the complex, multidisciplinary surgical management of a patient with multi-compartmental radiation-associated sarcoma of the left retroperitoneum occurring nearly 25 years after undergoing whole trunk radiation for Hodgkin's lymphoma.

Postoperative Quality of Life after Open Transinguinal Preperitoneal Inguinal Hernia Repair Using Memory Ring or Three-dimensional Devices

A transinguinal preperitoneal (TIPP) approach has become a common technique for inguinal hernia repair. Our goal was to compare the impact of the two mesh designs for this operation: a flat mesh with a memory ring device (MRD) or a three-dimensional device (3DD) containing both onlay and preperitoneal mesh components. The prospective International Hernia Mesh Registry (2007 to 2012) was queried for MRD and 3DD inguinal hernia repairs. Outcomes and patient quality of life (QOL), using the Carolinas Comfort Scale (CCS), were examined at 1, 6, 12, and 24 months. Standard statistical methods were used, and multivariate logistic regression was performed using a forward stepwise selection method. TIPP was performed in 956 patients. Their average age 57.4 ± 15.3 years, 94.0 per cent were male, and mean body mass index was 25.7 ± 3.2 kg/m2. MRD was used in 131 and 3DD in 825. Follow-up was 97, 82, 87, and 80 per cent at 1, 6, 12, and 24 months, respectively. Complications were not significantly different ( P > 0.05). Recurrence was 0.8 per cent for MRD and 2.1 per cent for 3DD ( P = 0.45). Comparing patient outcomes of MRD with 3DD at 1 month, 18.9 versus 11.5 per cent had symptoms of mesh sensation ( P = 0.02); 28.7 versus 14.8 per cent had movement limitations ( P < 0.01). MRD use was a significant independent predictor of movement limitation (odds ratio, 2.3; confidence interval, 1.4 to 3.7). No significant differences in CCS scores were seen at 6, 12, and 24 months. TIPP repair is safe and has a low recurrence rate. Early postoperative QOL is significantly improved with a 3DD mesh compared with MRD.

Defining surgical outcomes and quality of life in massive ventral hernia repair: an international multicenter prospective study

BACKGROUND

Our goal was to set criteria for massive ventral hernia and to compare surgical outcomes and quality of life after ventral hernia repair (VHR).

METHODS

The International Hernia Mesh Registry was queried for patients undergoing VHR from 2007 to 2013. Defect was categorized as massive if the width or length was greater than 15 cm or area greater than 150 cm(2). Massive VHR was compared to regular VHR.

RESULTS

A total of 878 patients underwent VHR: 436 open, 442 laparoscopic with 13 deaths (1.5%) and 45 hernia recurrences (5.1%). Of those, 158 patients (18%) met criteria for massive VHR. Massive VHR patients had longer length of stay (LOS) and operative time and more hematomas, wound infections, wound complications, and pneumonias (P < .05). On multivariate analysis, LOS was longer, and early postoperative pain and activity limitation were greater in massive VHRs (P < .01). Massive VHR in the laparoscopic approach resulted in greater long-term mesh sensation (P < .01).

CONCLUSIONS

VHR in massive hernias have increased rates of complications and longer LOS.

Impact of Implementing an Electronic Health Record on Surgical Resident Work Flow, Duty Hours, and Operative Experience

Our objective was to assess the effect of implementing an electronic health record (EHR) on surgical resident work flow, duty hours, and operative experience at a large teaching hospital. In May 2012, an EHR was put into effect at our institution replacing paper documentation and orders. Resident time to complete patient documentation, average duty hours, and operative experience before EHR and afterward (at 1, 4, 6, 8, and 24 weeks) were surveyed. We obtained 100 per cent response rate from 15 surgical residents at all time intervals. The average time spent documenting before EHR was 9 ± 2 minutes per patient document and at Weeks 1, 4, 6, 8, and 24 after EHR implementation was 22 ± 10, 15 ± 7, 15 ± 7, 14 ± 8, and 12 ± 4 minutes, respectively. Repeated measures analysis of variance demonstrated a difference among the means ( P < 0.0001). Discharge summary and operative note remained significantly longer to complete at Week 24 compared with paper documentation ( P < 0.05). Average resident work hours and operative cases per week before EHR were 77 ± 5 hours and 12 ± 5 cases, respectively, which were similar at all time points after EHR implementation ( P > 0.05). At 24 weeks after EHR, 74 per cent of residents felt their risk of performing a medical error using electronic documentation and order entry was higher compared with paper charting and orders. Transition to EHR led to a significant doubling in resident time spent performing documentation for each patient. It improved over 6 months after implementation but never reached the pre-EHR baseline for operative notes and discharge summaries. Average resident work hours and case logs remained similar during this transition.

Impact of implementing an electronic health record on surgical resident work flow, duty hours, and operative experience

Our objective was to assess the effect of implementing an electronic health record (EHR) on surgical resident work flow, duty hours, and operative experience at a large teaching hospital. In May 2012, an EHR was put into effect at our institution replacing paper documentation and orders. Resident time to complete patient documentation, average duty hours, and operative experience before EHR and afterward (at 1, 4, 6, 8, and 24 weeks) were surveyed. We obtained 100 per cent response rate from 15 surgical residents at all time intervals. The average time spent documenting before EHR was 9 ± 2 minutes per patient document and at Weeks 1, 4, 6, 8, and 24 after EHR implementation was 22 ± 10, 15 ± 7, 15 ± 7, 14 ± 8, and 12 ± 4 minutes, respectively. Repeated measures analysis of variance demonstrated a difference among the means (P < 0.0001). Discharge summary and operative note remained significantly longer to complete at Week 24 compared with paper documentation (P < 0.05). Average resident work hours and operative cases per week before EHR were 77 ± 5 hours and 12 ± 5 cases, respectively, which were similar at all time points after EHR implementation (P > 0.05). At 24 weeks after EHR, 74 per cent of residents felt their risk of performing a medical error using electronic documentation and order entry was higher compared with paper charting and orders. Transition to EHR led to a significant doubling in resident time spent performing documentation for each patient. It improved over 6 months after implementation but never reached the pre-EHR baseline for operative notes and discharge summaries. Average resident work hours and case logs remained similar during this transition.

Application of the resource-based relative value scale system to pediatrics

The majority of public and private payers in the United States currently use the Medicare Resource-Based Relative Value Scale as the basis for physician payment. Many large group and academic practices have adopted this objective system of physician work to benchmark physician productivity, including using it, wholly or in part, to determine compensation. The Resource-Based Relative Value Scale survey instrument, used to value physician services, was designed primarily for procedural services, leading to current concerns that American Medical Association/Specialty Society Relative Value Scale Update Committee (RUC) surveys may undervalue nonprocedural evaluation and management services. The American Academy of Pediatrics is represented on the RUC, the committee charged with maintaining accurate physician work values across specialties and age groups. The Academy, working closely with other primary care and subspecialty societies, actively pursues a balanced RUC membership and a survey instrument that will ensure appropriate work relative value unit assignments, thereby allowing pediatricians to receive appropriate payment for their services relative to other services.

Outcomes of pancreatic debridement in acute pancreatitis: analysis of the nationwide inpatient sample from 1998 to 2010

BACKGROUND

The objective of this study was to perform a national review of patients with acute pancreatitis (AP) who undergo pancreatic debridement (PD) to evaluate for risk factors of in-hospital mortality.

METHODS

The Nationwide Inpatient Sample was used to identify patients with AP who underwent PD between 1998 and 2010. Risk factors for in-hospital mortality were assessed with multivariate logistic regression.

RESULTS

From 1998 to 2010, there were 585,978 nonelective admissions with AP, of which 1,783 (.3%) underwent PD. From 1998 to 2010, the incidence of PD decreased from .44% to .25% (P < .01) and PD in-hospital mortality decreased from 29.0% to 15% (P < .05). Of patients undergoing PD, independent factors associated with increased odds of mortality were increased age (odds ratio [OR] 1.04, confidence interval [CI] 1.03 to 1.05; P < .01), sepsis with organ failure (OR 1.76, CI 1.24 to 2.51; P < .01), peptic ulcer disease (OR 1.83, CI 1.02 to 3.30; P < .05), liver disease (OR 2.27, CI 1.36 to 3.78; P < .01), and renal insufficiency (OR 1.78, CI 1.14 to 2.78; P < .05).

CONCLUSIONS

The incidence and operative mortality of PD have decreased significantly over the last decade in the United States with higher odds of dying in patients who are older, with chronic liver, renal, or ulcer disease, and higher rates of sepsis with organ failure.

The first nationwide evaluation of robotic general surgery: a regionalized, small but safe start

BACKGROUND

The purpose of this study was to evaluate the outcomes of the most commonly performed robotic-assisted general surgery (RAGS) procedures in a nationwide database and compare them with their laparoscopic counterparts.

METHODS

The Nationwide Inpatient Sample was queried from October 2008 to December 2010 for patients undergoing elective, abdominal RAGS procedures. The two most common, robotic-assisted fundoplication (RF) and gastroenterostomy without gastrectomy (RG), were individually compared with the laparoscopic counterparts (LF and LG, respectively).

RESULTS

During the study, 297,335 patients underwent abdominal general surgery procedures, in which 1,809 (0.6 %) utilized robotic-assistance. From 2009 to 2010, the incidence of RAGS nearly doubled from 573 to 1128 cases. The top five RAGS procedures by frequency were LG, LF, laparoscopic lysis of adhesions, other anterior resection of rectum, and laparoscopic sigmoidectomy. Eight of the top ten RAGS were colorectal or foregut operations. RG was performed in 282 patients (0.9 %) and LG in 29,677 patients (99.1 %). When comparing RG with LG there was no difference in age, gender, race, Charlson comorbidity index (CCI), postoperative complications, or mortality; however, length of stay (LOS) was longer in RG (2.5 ± 2.4 vs. 2.2 ± 1.5 days; p < 0.0001). Total cost for RG was substantially higher ($60,837 ± 28,887 vs. $42,743 ± 23,366; p < 0.0001), and more often performed at teaching hospitals (87.2 vs. 50.9 %; p < 0.0001) in urban areas (100 vs. 93.0 %; p < 0.0001). RF was performed in 272 patients (3.5 %) and LF in 7,484 patients (96.5 %). RF patients were more often male compared with LF (38.2 vs. 32.3 %; p < 0.05); however, there was no difference in age, race, CCI, LOS, or postoperative complications. RF was more expensive than LF ($37,638 ± 21,134 vs. $32,947 ± 24,052; p < 0.0001), and more often performed at teaching hospitals (72.4 vs. 54.9 %; p < 0.0001) in urban areas (98.5 vs. 88.7 %; p < 0.0001).

CONCLUSIONS

This nationwide study of RAGS exemplifies its low but increasing incidence across the country. RAGS is regionalized to urban teaching centers compared with conventional laparoscopic techniques. Despite similar postoperative outcomes, there is significantly increased cost associated with RAGS.

Postoperative quality of life after open transinguinal preperitoneal inguinal hernia repair using memory ring or three-dimensional devices

A transinguinal preperitoneal (TIPP) approach has become a common technique for inguinal hernia repair. Our goal was to compare the impact of the two mesh designs for this operation: a flat mesh with a memory ring device (MRD) or a three-dimensional device (3DD) containing both onlay and preperitoneal mesh components. The prospective International Hernia Mesh Registry (2007 to 2012) was queried for MRD and 3DD inguinal hernia repairs. Outcomes and patient quality of life (QOL), using the Carolinas Comfort Scale (CCS), were examined at 1, 6, 12, and 24 months. Standard statistical methods were used, and multivariate logistic regression was performed using a forward stepwise selection method. TIPP was performed in 956 patients. Their average age 57.4 ± 15.3 years, 94.0 per cent were male, and mean body mass index was 25.7 ± 3.2 kg/m(2). MRD was used in 131 and 3DD in 825. Follow-up was 97, 82, 87, and 80 per cent at 1, 6, 12, and 24 months, respectively. Complications were not significantly different (P > 0.05). Recurrence was 0.8 per cent for MRD and 2.1 per cent for 3DD (P = 0.45). Comparing patient outcomes of MRD with 3DD at 1 month, 18.9 versus 11.5 per cent had symptoms of mesh sensation (P = 0.02); 28.7 versus 14.8 per cent had movement limitations (P < 0.01). MRD use was a significant independent predictor of movement limitation (odds ratio, 2.3; confidence interval, 1.4 to 3.7). No significant differences in CCS scores were seen at 6, 12, and 24 months. TIPP repair is safe and has a low recurrence rate. Early postoperative QOL is significantly improved with a 3DD mesh compared with MRD.

Does ventral hernia defect length, width, or area predict postoperative quality of life? Answers from a prospective, international study

BACKGROUND

The goal of this study was to determine if ventral hernia defect length, width, or area predict postoperative pain and quality of life following ventral hernia repair (VHR).

METHODS

The International Hernia Mesh Registry, a prospective database from 40 institutions worldwide, was queried for patients undergoing VHR from October 2007 to June 2012. Laparoscopic and open VHR were evaluated separately. Width and length were stratified into large, ≥10 cm and small, <10 cm, along with area as large, ≥100 cm(2) and small, <100 cm(2).

RESULTS

In total, 865 International Hernia Mesh Registry patients underwent VHR. Large defect width, length, and area had no association with hernia recurrence or reoperation in both open and laparoscopic VHR. There was a significant increase in operating room time and length of stay for large compared with small width, length, and area for open and laparoscopic VHR patients (P < 0.05). Large area was associated with increased seroma and ileus in open and laparoscopic VHR (P < 0.05). There was greater pain and activity limitation at 1 mo for large versus small width and area whether repaired laparoscopically or open (P < 0.05). When comparing large to small length, there was no difference in pain for all follow-up time points when repaired laparoscopically, but there is significantly increased odds of pain and activity limitation at 1, 6, and 12 mo when repaired open (P < 0.05).

CONCLUSIONS

Patients undergoing laparoscopic or open VHR with large defect widths and total area have a greater chance of pain and activity limitation at 1-mo follow-up, but not long term. Large defect lengths are associated with increased early and chronic discomfort in open VHR only.

Preliminary results of surgical and quality of life outcomes of Physiomesh in an international, prospective study

Physiomesh is a novel, lightweight, large pore, polypropylene mesh designed to have flexibility that matches the compliance of the abdominal wall in an effort to improve patient quality of life (QOL). The International Hernia Mesh Registry was queried for ventral hernia repair (VHR) and inguinal hernia repair (IHR) with Physiomesh. Demographics, operative and postoperative details, and the Carolinas Comfort Scale (CCS) as a measure of QOL were recorded. Physiomesh was used in 100 patients, 29 IHR and 71 VHR. Their average age was 56.8 +/- 13.7, and BMI was 34.0 +/- 21.0 kg/m2. For IHR, preoperative pain (CCS > or = 2) was present in 41%, but decreased at 1, 6, and 12 months postoperatively to 25.9%, 0%, and 1.6%, while movement limitation decreased from 42.9% to 18.5%, 1.6%, and 3.1%. There were no complications or recurrences. The average VHR measured 66.4 cm2; 93% underwent a laparoscopic repair. Pain was present in 59.1% preoperatively but 21% at 12 months. Movement limitations reduced from 43.2% to 15.8% at 12 months. Mesh sensation was reported in only 10.5% at 1 year. There was 1 recurrence. Physiomesh is well tolerated by patients undergoing IHR and VHR. It is associated with a very favorable long-term QOL.

Splenectomy ameliorates hematologic toxicity of hyperthermic intraperitoneal chemotherapy

BACKGROUND

Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy is a promising modality for peritoneal carcinomatosis. Splenectomy is frequently required, however effect upon hematotoxicity is unknown.

METHODS

195 patients undergoing the procedure were evaluated and granulocyte colony stimulating factor administered for white blood cell counts <4.0.

RESULTS

52% of 195 underwent splenectomy; average white blood cell and platelet nadirs were 6.1,172. Non-splenectomy patients averaged white blood cell nadir 4.6, platelet nadir 164.1. Granulocyte colony stimulating factor administered in 29% of splenectomy, 43% of non-splenectomy (P=0.043).

CONCLUSION

Splenectomy ameliorates hematotoxicity of hyperthermic intraperitoneal chemotherapy and significantly reduces post-operative granulocyte colony stimulating factor requirements.

Documentation of asthma severity in pediatric outpatient clinics

National asthma guidelines recommend assessment and documentation of asthma severity at each clinic visit. A cross-sectional medical record review was conducted, which found that only 34% of records had any documentation of severity in the previous 2 years. However, severity documentation is associated with other indicators of quality care such as receipt of an action plan, spacer device, peak flow meter, asthma education, and influenza vaccination. These results suggest that use of a system for classifying asthma severity compels the physician to consider the long-term management of asthma, rather than just acute treatment of the disease. Interventions to improve physician practice should continue to emphasize severity assessment.

Is the P25L a "real" VHL mutation?

BACKGROUND

The von Hippel-Lindau (VHL) gene has two translational initiation sites separated by 53 codons. Both proteins have been detected in cells and have equivalent activity. A mutation in the first 53 codons of the open reading frame has no effect on the structure of the smaller protein. As expected, the vast majority of VHL mutations are downstream of the second initiation site and alter both proteins. However, several candidate mutations have been found in the first 53 codons, including a substitution of leucine for proline at position 25 (P25L) of the larger protein.

METHODS AND RESULTS

DNA sequence analysis showed two VHL gene mutations, P25L and P86R, in an individual with a clinical diagnosis of VHL disease. Both mutations have been reported previously. P25L alters only the upstream protein, whereas P86R alters both VHL proteins. Based on the positions of the mutations, P86R is more likely to be pathogenically significant than the P25L mutation. A survey of anonymized DNAs for P25L, using allele-specific PCR, revealed that it is a variant with an allele frequency of approximately 0.5%.

CONCLUSION

P25L is a rare variant of the VHL gene and cannot be considered a cause of VHL disease. However, this work does not prove that P25L is entirely innocuous.

Two distinct phenotypes caused by two different missense mutations in the same codon of the VHL gene

We have identified a family segregating von Hippel-Lindau (VHL) disease with a previously unreported T547A mutation in exon 1 of the VHL gene that causes a Tyr112 to Asn missense alteration in the protein. The mutation was identified by nucleotide sequencing and confirmed by restriction enzyme digestion. The mutation cosegregated with the disease in all five tested affected individuals from the extended family. The family consists of more than 100 at-risk individuals over seven generations. To date, we have identified 13 affected individuals of whom seven have had renal cell carcinoma and one has had a pheochromocytoma. No other case of a neuroendocrine tumor of the pancreas or adrenal gland (pheochromocytoma) was found or recognized retrospectively. Other manifestations in this family include retinal angioma and hemangioblastoma of the central nervous system. We also found the T547A mutation in three asymptomatic members of the family, ages 12, 19, and 20. Another mutation, T547C, which causes Tyr112 to His, has been seen at the same position and has been associated with VHL type 2A (pheochromocytoma, but no renal cell carcinoma) in two families with a total of 22 affected individuals [Chen F, Slife L, Kishida T, Mulvihill J, Tisherman SE, Zbar B, 1996: J Med Genet 33:716-717]. Thus, different amino acid changes at the same position can cause very distinct clinical phenotypes. It will be interesting to elucidate the functional differences that underlie the different phenotypes.

Simultaneous detection of five mutations in the steroid 21-hydroxylase gene using nested allele-specific amplification

Congenital adrenal hyperplasia due to deficiency of steroid 21-hydroxylase (CYP21) is most frequently due to mutations that arise from the nearby CYP21 pseudogene. The mechanism involves either unequal crossing over, which deletes part of the CYP21 functional gene, or gene conversion which puts a mutation from the pseudogene into the functional gene. We have devised an assay to rapidly screen for five known mutations that are due to gene conversion within an 1,800 bp region of the CYP21 gene--I172N, V281L, Q318X, R356W, and a cluster of mutations in exon 6 (I236N, V237E, M239K). This method is based on a set of nested allele-specific polymerase chain reactions done simultaneously in one tube, for which we suggest the acronym NASA, for nested allele-specific amplification. The assay is capable of detecting the mutations individually as well as all combinations of mutations tested.

Processed pseudogene from the von Hippel-Lindau disease gene is located on human chromosome 1

The von Hippel-Lindau (VHL) disease gene is a tumor suppressor located at 3p25-26. While amplifying intron 1 of this gene, a smaller-than-expected product was found. This fragment was sequenced and was approximately 78% similar in sequence to the VHL gene and completely lacked sequence from the intron. No stop codons were found in the sequenced region. Using this DNA fragment as a probe for Northern blot hybridization analysis, no evidence was found for expression of a unique RNA. Because of the lack of intron 1 sequence and the likely lack of expression, the new sequence is most probably a part of a VHL processed pseudogene. The putative pseudogene was mapped to human chromosome band 1q12 using the polymerase chain reaction with template DNA from human/rodent somatic cell hybrids, a radiation hybrid panel, and a set of primers that were chosen to be maximally divergent from the genuine VHL gene. The human/rodent somatic cell hybrid DNAs were then used on Southern blots to determine which human bands are from the pseudogene and which are from the functional gene. This knowledge is valuable in interpreting Southern blot evidence of VHL gene abnormalities.

A deletion polymorphism due to Alu-Alu recombination in intron 2 of the retinoblastoma gene: association with human gliomas

The retinoblastoma gene (RB) encodes a tumor suppressor that is inactivated in a number of different types of cancer. We searched for gross alterations of this gene in tumors of the central nervous system by using Southern blot hybridization. A common alteration was found in several tumors and was mapped to the region around exon 2. Nucleotide sequencing showed that the alteration was caused by a 799-bp deletion in intron 2 of the RB gene and was probably due to homologous recombination between two Alu repeats. Deletions of this type have not been found previously in the RB gene. The deletion turned out to be a polymorphism with an allele frequency estimated at 2.2% in 185 patients without cancer. The deletion was found in five of 48 patients with brain tumors (allele frequency of 5.2%). This difference is not statistically significant (P = 0.149, Fisher's exact test). Confining the analysis only to glioma brain tumors revealed a statistically significant difference compared with the cancer-free patient controls (P = 0.027, Fisher's exact test). Further study is needed to determine if the deletion is a weak brain cancer-predisposing mutation or a harmless polymorphism. Finding this mutation in a tumor and the germline DNA of a retinoblastoma patient could lead to incorrect estimation of the heritability of a tumor.

Bloodstream invasion in early Lyme disease: results from a prospective, controlled, blinded study using the polymerase chain reaction

PURPOSE

The purposes of this study were to determine (1) the optimal techniques for and potential diagnostic usefulness of the polymerase chain reaction (PCR) in early Lyme disease, and (2) the true frequency and clinical correlates of PCR-documented blood-borne infection in the dissemination of Lyme disease.

PATIENTS AND METHODS

We performed a prospective, controlled, blinded study of PCR, culture, and serology on fractionated blood samples from 105 patients; 76 with physician-diagnosed erythema migrans and 29 controls. Clinical characteristics of the patients were obtained with a standardized data entry form and correlated with results of the laboratory studies.

RESULTS

Only 4 of the 76 (5.3%) patients with erythema migrans were culture positive; however, 14 of 76 (18.4%) had spirochetemia documented by PCR of their plasma. None of 29 controls were PCR or culture positive (P = 0.007, versus patients). PCR-documented spirochetemia correlated with clinical evidence of disseminated disease; 10 of 33 patients (30.3%) with systemic symptom(s) were PCR positive compared to 4 of 43 (9.3%) without such evidence (P = 0.02). PCR positivity was more frequent among patients with each of four specific symptoms: fever, arthralgia, myalgia, and headache (all P < 0.05). A higher total number of symptoms (median 2.5 in PCR-positive patients versus 0 in PCR-negative controls; P < 0.01) and the presence of multiple skin lesions (37.5% of patients with multiple, versus 13.3% of patients with single lesions [P = 0.04] were also correlated with PCR positivity. Patients with both systemic symptoms and multiple skin lesions had a 40% PCR-positivity rate; however, 4 of 42 (9.5%) asympatomatic patients with only single erythema migrans lesions were also PCR positive. In multivariate analysis using logistic regression, the number of systemic symptoms was the strongest independent predictor of PCR positivity (P = 0.004).

CONCLUSIONS

PCR detection of Borrelia burgdorferi is at least three times more sensitive than culture for identifying spirochetemia in early Lyme disease and may be useful in rapid diagnosis. PCR positivity significantly correlates with clinical evidence of disease dissemination. Bloodstream invasion is an important and common mechanism for the dissemination of the Lyme disease spirochete.

The persistence of spirochetal nucleic acids in active Lyme arthritis

Six of seven patients with Lyme arthritis were positive by PCR. In contrast, all 18 synovial fluid samples from patients with other disorders, including rheumatoid arthritis, spondyloarthropathy, gout, pseudogout, hemarthrosis, degenerative joint disease, lupus, papillary synovitis, and trauma, were negative by PCR (P < 0.001, Lyme arthritis compared with controls, Fisher exact test). All 38 laboratory controls were negative by PCR. The assay reproducibly detected 20 or fewer B. burgdorferi cells directly or when added to extracted synovial fluid that was previously negative by PCR. Polymerase chain reaction was done four times with identical results, including analyses with both outer surface protein A primer sets.

Sodium butyrate causes an increase in the block to transcriptional elongation in the c-myc gene in SW837 rectal carcinoma cells

Elevated expression of the c-myc oncogene is a frequent finding in tumors and cell lines derived from carcinomas of the colon and rectum. In a previous study we demonstrated that the differentiation agent sodium butyrate causes a rapid reduction in the expression of c-myc RNA in the rectal carcinoma cell line SW837. This effect was blocked by inhibitors of protein synthesis, suggesting that butyrate causes the induction of an activity that has a negative effect on c-myc expression. In the present work we demonstrate that the rapid decrease in the level of c-myc RNA, upon treatment of SW837 cells with 2 mM butyrate, is followed by a slower decrease in the level of p53 RNA and an increase in the RNA levels for fibronectin and a placental type alkaline phosphatase. Using in vitro elongation of nascent transcripts to measure transcription and actinomycin D chase experiments to measure RNA stability, we show that the reduction in expression of c-myc RNA is due to an increase in the block to transcriptional elongation, rather than a decrease in transcriptional initiation or an increase in degradation of the RNA. We conclude that sodium butyrate induces an activity that increases the transcriptional block in SW837 cells, and that regulation of transcriptional elongation is an important mechanism for regulating c-myc expression in this cell type. A shift in relative usage of the two major promoters in the c-myc gene accompanies the reduction in expression. The potential significance of this finding with respect to transcriptional elongation is discussed. Mutations in the exon 1/intron 1 boundary region of the c-myc gene cause an increase in transcriptional elongation in Burkitt lymphoma. We sequenced this region in a series of cell lines derived from colorectal carcinomas, all of which had an elevated level of c-myc expression, to determine if a similar mutational mechanism is at work in this disease. All of the lines examined had a normal c-myc DNA sequence, suggesting that the deregulation of c-myc expression in colon cancer is not due to a cis mutation in this region.

Hypermutation of the MYC gene in diffuse large cell lymphomas with translocations involving band 8q24

The sequence of the exon 1/intron 1 boundary region of the MYC gene was determined in two diffuse large cell lymphomas (DLCL), one with t(8;14) (q24;q32) and the other with t(8;22) (q24;q11). Both tumors had multiple mutations in this region. Also, both tumors had mutations in the protein binding site in intron 1, which is a frequent target for mutational inactivation in endemic Burkitt's lymphoma (eBL). The translocations at 8q24, and multiple mutations in the exon 1/intron 1 boundary region, are reminiscent of similar findings in eBL. The same underlying oncogenic event that occurs in most eBLs is thus found in some DLCLs.

Collagen stimulating factors in hepatic fibrogenesis

Four factors which stimulate collagen synthesis and prolyl hydroxylase activity in cultures of human and mouse fibroblasts have been isolated by molecular sieve chromatography from animal and human fibrotic and cirrhotic livers. These factors do not stimulate protein or DNA synthesis or total DNA in these cultures. It has also been shown that these factors, designated collagen stimulating factors F1-F4, do not owe their activity to ascorbate or glutamine. Collagen stimulating factors are heat stable, and F1 and F2 have apparent molecular weights of about 4000 and 1000 respectively. Since these factors are not present in normal animal or human liver it is suggested that they may be responsible for increased collagen production in vivo in hepatic fibrosis and cirrhosis.

Isolation of collagen stimulating factors from healing wounds

Five factors (collagen stimulating factors) have been isolated from healing murine skin wounds which stimulate prolyl hydroxylase activity and collagen synthesis in mouse fibroblasts in vitro. These factors stimulate general protein synthesis to a much smaller extent. Collagen stimulating factors are detectable in wounds three days after healing begins and disappear after six days when healing is complete. These data indicate that these factors may modulate collagen production during wound healing.

Tissue culture, protein and collagen synthesis in antibiotic sterilized canine heart valves

Viability of canine heart valve leaflet fibroblasts was assessed after varying periods of sterilization and storage in antibiotic-nutrient solution. Tissue culture and assessment of protein and collagen synthesis showed that tissue obtained under optimal conditions rarely retains viability beyond 3 weeks in antibiotic-nutrient solution and is severely impaired after 2 weeks. This casts serious doubts on viability in current clinical homograft valve practice.

Viability in human heart valves prepared for grafting

Viability of antibiotic sterilized and stored human heart valves obtained at routine necropsy was assessed by tissue culture and protein and collagen synthesis. Only three of 23 valves examined showed any evidence of viability, in striking contrast to earlier work on canine valves obtained under optimal conditions. These findings justify doubts regarding pre-implantation viability in human heart valves prepared for grafting.