Clinical and Molecular Determinants of PSA Response to Bipolar Androgen Therapy in Prostate Cancer

BACKGROUND

Bipolar Androgen Therapy (BAT) is a novel therapy known to be effective in a subset of men with metastatic castrate resistant prostate cancer (mCRPC). A better understanding of responders and non-responders to BAT would be useful to clinicians considering BAT therapy for patients. Herein we analyze clinical and genetic factors in responders/non-responders to better refine our understanding regarding which patients benefit from this innovative therapy.

METHODS

mCRPC patients were assessed for response or no response to BAT. Patients with PSA declines of greater than 50% from baseline after 2 or more doses of testosterone were considered to be responders. Whereas, Non-responders had no PSA decline after 2 doses of testosterone and subsequently manifest a PSA increase of >50%. Differences between these two groups of patients were analyzed using clinical and laboratory parameters. All patients underwent genomic testing using circulating tumor DNA (ctDNA) and germline testing pre-BAT.

RESULTS

Twenty five patients were non-responders and 16 were responders. Baseline characteristics between non-responders and responders varied. Responders were more likely to have had a radical prostatectomy as definitive therapy and were more likely to have been treated with an androgen receptor (AR) antagonist (enzalutamide or apalutamide) immediately prior to BAT (compared to abiraterone). Duration of prior enzalutamide therapy was longer in responders. Non-responders were more likely to have bone-only metastases and responders were more likely to have nodal metastases. Assays detected ctDNA AR amplifications more often in responding patients. Responders trended toward having the presence of more TP53 mutations at baseline.

CONCLUSIONS

BAT responders are distinct from non-responders in several ways however each of these distinctions are imperfect. Patterns of metastatic disease, prior therapies, duration of prior therapies, and genomics each contribute to an understanding of patients that will or will not respond. Additional studies are needed to refine the parameters that clinicians can utilize prior to choosing among the numerous treatment alternatives available for CRPC patients. This article is protected by copyright. All rights reserved.

Comparative ctDNA analyses of African-American and Caucasian patients with CRPC

24

Background: Somatic genetic analyses have indicated genetic distinctions in AA as compared to C patients. In the Mahal et al. study (1) evaluating a broad spectrum of pts with tissue based assays, FOXA1 mutations were more frequent in AA men and TP53 mutations were less frequent in AA men as compared to C men. In a separate analysis by Khashab et al. (2) conducted in prostate cancer pts receiving androgen deprivation therapy, using both tissue and ctDNA assays, the authors reported AR, TP53, SPOP, and BRCA2 were more frequently mutated in AA men as compared to C men. Herein we assessed the Guardant 360 platform in assessing ctDNA differences in AA and C men, all of whom had CRPC at the time assays were performed. Methods: Guardant 360 was used to analyze ctDNA with a cut-off of >0.5% for allelic fractions for ascertaining the presence or absence of pathogenic mutations and various amplifications. Lower allelic fractions were not analyzed given these may represent less relevant mutations. Depending on the timing of the assays (2015-2021), 70-83 genes were analyzed. All pts had CRPC and all patients were treated at Tulane Cancer Center. Chi Square analyses were used to determine statistical differences. AR, BRCA2, and TP53 were assessed but SPOP and FOXA1 were not assessable in the Guardant ctDNA assay. Both mutations and amplifications were evaluated. Results: Among men with CRPC, a total of 48 AA men and 179 C men were analyzed using ctDNA. Clear distinctions were found in the alteration reported in APC, TP53, and CDK12. TP53 was less frequently mutated and other genes were more frequently altered in the AA men. Conclusions: Using Guardant ctDNA assays in men with CRPC, clear distinctions were found in AA men as compared to C men. It is unclear why these results differ from that reported by others, however distinctions in both the assays and the populations are notable.[Table: see text]

Longitudinal ctDNA alterations in germline positive CRPC patients

275

Background: Circulating tumor-derived DNA (ctDNA) is an accessible method for characterizing somatic alterations. We report longitudinal ctDNA screenings of mCRPC patients (pts) who have had germline testing. Methods: Patients with both germline testing and ctDNA assessment were included. Germline testing was performed with a multi-gene cancer panel from Invitae (50-83 genes) and somatic alterations in ctDNA were identified by testing with Guardant 360 (70-83 genes). ctDNA alterations were characterized as deletions, frameshift, missense, nonsense, and other mutations. A total of 177 patients in various stages of therapy had both ctDNA and germline DNA tested. Results: From 2015-2021, 177 mCRPC patients were included and had an average of 3 ctDNA tests. 11.3% (20/177) had pathogenic or likely-pathogenic germline mutations. The common pathogenic germline mutations were in BRCA2 (25%; 5/20), ATM (10%; 2/20), and MSH2 (10%; 2/20). In ctDNA, missense mutations were the most prevalent type of gene alteration in germline negative (n = 539/790, 68%) and germline positive (n = 124/218, 57%) followed by frameshift mutations at 22% (n = 48/218) in germline positive and 10% (n = 80/790) in germline negative patients. Germline positive patients were more likely to have somatic frameshift mutations (OR = 2.09, 95% C.I. (1.3792, 3.1618), p = 0.001) and less likely to have missense mutations (OR = 0.61, 95% C.I. (0.4519, 0.8351), p = 0.002). Other alterations including deletions, nonsense, and other mutations were not significantly different. Of the germline positive pts, BRCA2 mutation was associated with the highest number of somatic alterations. Conclusions: Germline positive CRPC patients were more likely to have frameshift mutations and less likely to missense mutations compared to germline negative CRPC patients. Patients with germline mutations in BRCA2 and TP53 had the highest number of somatic alterations detected in ctDNA over the course of ctDNA evaluation.

Evaluation of ctDNA alterations in mCRPC patients with germline pathogenic mutations

177

Background: Germline alterations are found in approximately 12-17% of CRPC patients. Similarly, evaluating tumoral changes with circulating tumor DNA (ctDNA) has become an increasingly useful tool for understanding mechanisms underpinning disease progression. In this study, we evaluated both germline and somatic genetic changes in patients with mCRPC. Methods: Patients included had germline screening and ctDNA analyzed with the Guardant 360 assay. All patients were CRPC at the time of Guardant testing. Germline alterations were classified as pathogenic/likely-pathogenic or not pathogenic. Only ctDNA alterations with an alleleic fraction greater than 0.5% were included in analyses. Additional evaluation of CRPC status, treatment history, family history and other clinical covariates are ongoing. Chi-square and Fischer’s Exact tests were used for comparison of cohorts. Results: A total of 168 Caucasian CRPC patients had Guardant 360 testing at time of progression and germline testing between 2015-2021. 61% (n = 102/168) of patients have previously had treatment with abiraterone, 49% (n = 82/168) have had Enzalutamide and 40% (n = 68/168) have had treatment with taxanes. 12% (n = 20/168) of CRPC patients had a pathogenic/likely-pathogenic (P/LPv) germline alteration, 46% (n = 77/168) had a germline variant of unknown significance (VUS), 42% (n = 71/168) were germline negative. CRPC patients with pathogenic germline mutations were significantly more likely to have subsequent somatic alterations in BRCA2 (OR = 5.05, 95% C.I. (1.11, 23.01), p = 0.055), NF1 (OR = 7.89, 95% C.I. (2.15, 28.10), p = 0.004), and TP53 (OR = 3.52, 95% C.I. (1.28, 9.68), p = 0.015). In TP53, among germline positive patients, 45% (n = 9/20) had TP53 alterations compared to 30% (n = 45/148) of germline negative patients. Conclusions: Germline positive (P/LPv) CRPC patients were significantly more likely to have somatic alterations in BRCA2, NF1, and TP53. Understanding the totality of genetic changes, both germline and acquired somatic alterations is essential as the arsenal of targeted treatment for CRPC continues to expand. Additional studies including longitudinal assessment genetic changes and clinical correlates will be necessary to evaluate these findings in the context of treatment outcomes and disease progression.

68ga-PSMA-11 patients with newly diagnosed and recurrent prostate cancer (Firefly)

TPS189

Background: A primary challenge facing oncologists is the accurate identification of the source of the rising PSA in the recurrent disease setting and the failure of proper staging at the time of initial therapy. Current imaging modalities perform poorly in this regard. PSMA imaging is FDA approved but reimbursement remains a considerable issue for most patients. Methods: This is a phase II expanded access intermediate sized clinical trial using 68Ga-PSMA-11 (Telix Pharma cold kit) under our own Investigational New Drug (IND) with the FDA. Two cohorts are utilized, recurrent disease with a PSA > 0.2 or > 2.0 post-radiation, and newly diagnosed high risk localized disease and/or oligo-metastatic patients as assessed by conventional imaging. 300 patients will be allowed to enroll and 63 are enrolled to date. Patients will be injected with 1.8–2.2 MBq/kg body weight with 68Ga-PSMA-11 (per EANM guidelines). The lower and upper limits of the dose are set to 3 to 7 mCi respectively. Primary Objective(s): Utilize 68Ga-PSMA-11 PET images to define uptake location for localization of prostate cancer metastatic sites in patients prior to initial therapy and to utilize 68Ga-PSMA-11 PET images to define uptake location for localization of prostate cancer including both local recurrences and metastatic sites in patients with recurrent disease after initial therapy. Secondary Objectives: To assess the therapeutic consequences of 68Ga-PSMA-11 PET/CT imaging in prostate cancer patients with and without prior treatment. As such the planned therapies after the PSMA scan will be annotated and recorded. In addition, we aim to determine the number of patients with metastatic disease prior to initial therapy that was not diagnosed with conventional imaging and we aim to determine the locations of recurrent disease for those patients who have demonstrated PSA recurrence after curative therapy. Percentage of positive scans will be assessed for PSA values 0.2-0.5 ng/mL, > 0.5-1.0 ng/mL, > 1.0- > 2.0 ng/mL, and > 2 ng/mL. Results will be summarized descriptively with 95% confidence intervals. Localization of all lesions will be performed with regard to lymph nodes (pelvic versus non-pelvis), bones (by location), and other (by site). Treatment planning will be captured and quantified by radiation, surgery, hormonal therapy (type and duration), and/or observation at the time of the initial clinical visit after the PSMA scan and 6 months later. This trial is open and recruiting patients. Data analysis has not been performed. Clinical trial information: NCT04854369.

Circulating tumor DNA responses to high-dose testosterone injections in CRPC patients

173

Background: Some proportion of men with CRPC have favorable responses to high doses of testosterone (HDT) and some do not. Genomic determinants of these responders and non-responders are poorly understood. Herein ctDNA predictors of response are assessed using a responder/non-responder analysis. Methods: All men with CRPC had been pretreated with abiraterone, enzalutamide, or both. A ctDNA test was obtained prior to high doses of testosterone (administered as a dose of 400 mg IM testosterone cypionate every 3-4 weeks). Guardant 360 was used to analyze ctDNA (with an allelic fraction cut-off of > 0.5%) to ascertain the presence or absence of pathogenic mutations. Lower allelic fractions were not analyzed. Responders had a PSA decline of 50% or more (N = 16), non-responders received at least two doses of testosterone but never had any PSA decline at all (N = 20). All patients were treated at Tulane Cancer Center. Results: AR amplifications were more commonly detected (p = 0.036) pre-treatment in the ctDNA of responders (5/16) as compared to non-responders (1/20). No differences were found in those with common AR mutations; T878A was detected in 2/16 responders and 2/20 non-responders, L702H was detected in 1/16 responders and 2/20 non-responders. No differences were seen with regard to TP53 mutations, 6/20 non-responders and 7/16 responders. Non- AR/non- TP53 mutations were not distinct in the two groups but trended (P = 0.15) toward being more common in non-responders (5/16 in responders versus 11/20 non-responders). Pre- and post- ctDNA analyses were conducted in 5/6 patients for those with AR amplification at baseline. In all 5 of these patients, the degree of AR amplification diminished after testosterone injections. Conclusions: In this analysis of CRPC patients who were responders and non-responders to 400 mg testosterone cypionate q 3-4 weeks (post-abiraterone and/or enzalutamide), only AR amplifications in ctDNA were predictive of response. In all measured patients, the degree of AR amplification in the ctDNA diminished after testosterone injections.

PD-L1 inhibition with avelumab plus abiraterone acetate or enzalutamide in African Americans with metastatic castrate-resistant prostate cancer (mCRPC)

87

Background: African Americans (AA) are at higher risk for prostate cancer death compared to other ethnic groups in the United States. Early immune-based therapy prolonged overall survival in men with mCRPC and appears to be more pronounced in AA compared to Caucasian men. We sought to explore efficacy of PD-L1 inhibition in AA men with mCRPC. Methods: AA men > 18 years of age and had developed mCRPC on next generation hormonal therapies (NHTs) were eligible for this study. Patients received avelumab 10mg/kg IV every 2 weeks while remaining on NHTs until clinical or radiographic disease progression. This pilot, single-arm phase 2 prospective study was designed to enroll 13 patients with primary endpoint to assess > 50% reduction in PSA (PSA50). Radiographic assessments were planned every 12 weeks until progression or two years, whichever came first. Results: Of the eight patients enrolled, there were three screen-failures: +hepatitis titer (n = 1), rapid clinical deterioration (n = 1) and not confirmed CRPC (n = 1). Median age at time of enrollment was 62 (54-73) with median PSA 7.2 (3.6 – 8.63). Five patients received at least one dose of avelumab and remained on abiraterone acetate with steroid (n = 4) or enzalutamide (n = 1). Median duration on NHTs prior to enrollment was 364 days (95% CI, 260.9-467.1). Median time from screening to cycle 1 was 8 days (3-14). One patient withdrew consent after a single dose of avelumab. Two patients had rapid clinical progression within 8 weeks of starting avelumab. One patient received 9 cycles of avelumab and progressed. One patient experienced a grade 4 adverse event after 2 doses of avelumab with clinical progression during treatment delay. None of the five enrolled patients achieved a PSA50. The median time on study to PSA progression was 35 days (95 CI%, 0-94.8) with median time to radiographic progression of 44 days (95 CI%, 0-118.5). Adverse events occurred in 80% (n = 4/5) of cases. One of the 11 reported grade 3/4 adverse events was related to study drug (G3 hyperglycemia). The study was closed to further accrual prior to the pre-planned completion due to safety concerns related to lack of efficacy of study intervention and rapid clinical progression. Conclusions: The addition of avelumab did not demonstrate clinical activity in AA men with mCRPC who progressed on abiraterone acetate or enzalutamide. The short time interval between PSA progression and radiographic and/or clinical progression is concerning and notable to be much shorter than previously reported pivotal phase III trials. This suggests potential for very significant clinical implications regarding not only future clinical trial designs but also clinical management in this underrepresented ethnicity. We will report updated analysis with longer follow-up (NCT03770455). Clinical trial information: NCT03770455.

18F-fluciclovine positron emission tomography (PET) in metastatic castration-resistant prostate cancer (mCRPC) treated with abiraterone acetate

TPS171

Background: Conventional imaging of prostate cancer has limitations in staging, restaging after biochemical relapse, and response assessment. Functional imaging with positron emission tomography (PET) can target various aspects of tumor biology and has shown to be superior in the detection of prostate cancer compared with conventional computed tomography (CT) and bone scans. 18F-Fluciclovine, a synthetic amino acid transported across mammalian cell membranes by amino acid transporters that is upregulated to a greater extent in prostate cancer cells than in surrounding tissue, is currently approved for PET imaging for patients with biochemical recurrence. The role of 18F-Fluciclovine PET scans in monitoring response to novel hormonal therapies such as abiraterone acetate is unclear. We hypothesize that 1) using 18F-Fluciclovine PET scanning will allow a more sensitive assessment of mCRPC patients at the initiation of systemic therapy with abiraterone acetate and 2) the changes observed in 18F-Fluciclovine PET will correlate better with the serologic changes in PSA, allowing superior disease monitoring, than conventional imaging modalities. Methods: This single-arm, pilot study (NCT04158245) will describe the changes in 18F-Fluciclovine PET scan and compare these results with PSA and conventional computerized tomography (CT) and bone scans, in mCRPC patients treated with abiraterone acetate plus prednisone. Patients must have a detectable baseline PSA of ≥ 2 ng/mL and metastatic disease detected on conventional CT and bone scans. The use of docetaxel in the hormone-sensitive setting is allowed. Twelve patients will be treated with abiraterone 1000 mg daily plus prednisone 5 mg (or dexamethasone 0.5 mg) daily for mCRPC and get 18F-Fluciclovine PET and conventional CT and bone scans at baseline and 12 weeks after starting abiraterone therapy or at disease progression. PSA progression will be defined as a repeated increase in PSA of at least 2 ng/dL and 25% from nadir values, at least 1 week apart, according to PCWG3 criteria and clinical or radiographic progression by RECIST version 1.1. The co-primary objectives of the study include the 18F-Fluciclovine PET changes at baseline and 12 weeks after abiraterone acetate for mCRPC and the comparison between 18F-Fluciclovine PET and conventional scans. Secondary and exploratory endpoints include PSA response, PSA progression and genomic alterations by next-generation sequencing. As of 12 September 2020, this trial is actively enrolling. Clinical trial information: NCT04158245.

Outcomes With First-Line PD-1/PD-L1 Inhibitor Monotherapy for Metastatic Renal Cell Carcinoma (mRCC): A Multi-Institutional Cohort

Introduction: The treatment landscape of metastatic renal cell carcinoma has advanced significantly with the approval of combination regimens containing an immune checkpoint inhibitor (ICI) for patients with treatment-naïve disease. Little information is available regarding the activity of single-agent ICIs for patients with previously untreated mRCC not enrolled in clinical trials. Methods: This retrospective, multicenter cohort included consecutive treatment-naïve mRCC patients from six institutions in the United States who received ≥1 dose of an ICI outside a clinical trial, between June 2017 and October 2019. Descriptive statistics were used to analyze outcomes including objective best response rate (ORR), progression-free survival (PFS), and tolerability. Results: The final analysis included 27 patients, 70% men, median age 64 years (range 42-92), 67% Caucasian, and 33% with ECOG 2 or 3 at baseline. Most patients had intermediate risk (85%, IMDC) with clear cell (56%), papillary (26%), unclassified (11%), chromophobe (4%), and translocation (4%) RCC. All patients had evidence of metastatic disease involving the lungs (59%), lymph node (41%), CNS (19%), liver (11%), adrenal gland (11%), and bone (11%). The median time on ICI was 3.1 (0.1-26.8) months, and the median PFS was 6.3 (95% CI, 0-18.6) months. Among the 21 patients with an evaluable response, the best ORR was 33%, including two complete responses and five partial responses. The ORR was 29% (n = 1 complete response, n = 5 partial response) in clear cell and 5% (n = 1 complete response) in non-clear cell RCC. Adverse events (AEs) of any cause were reported in 37% and included fatigue (11%), dermatitis (11%), diarrhea (7%), and shortness of breath (7%). Significant AEs (30%) included shortness of breath (7%), acute kidney injury (4%), dermatitis (4%), Clostridium difficile infection (4%), cerebrovascular accident (4%), and fatigue (7%). Three patients discontinued therapy due to grade 4 AEs. Conclusions: In this multi-institutional case series, single-agent ICI demonstrated objective responses and was well tolerated in a heterogeneous treatment-naïve mRCC cohort. ICI monotherapy is not the standard of care for patients with mRCC, and further investigation is necessary to explore predictive biomarkers for optimal treatment selection in this setting.

Sensitive rapid detection method for viable bacterial cells

A rapid sensitive method for the detection of viable bacterial cells is described in which P as inorganic orthophosphate is used to label the cells. Factors affecting the uptake of P by cells as well as the sensitivity of the method have been explored with suspensions of Aerobacter aerogenes. The uptake of PO(4) is dependent on several factors. Of various incubation media tested, one composed of 0.005 m KCl, 0.002 m MgSO(4) and 10 mg/ml of glucose was found to best stimulate the uptake of the tracer. Incubation time and temperature and level of isotope and of unlabeled P also affected uptake. Labeled cells were collected on a membrane filter for measurement of radioactivity. Under optimal conditions, as few as 23 viable cells per milliliter were detected in 1 hr with 95% confidence.

Galantamine in frontotemporal dementia and primary progressive aphasia

BACKGROUND/AIMS

The treatment of frontotemporal dementia (FTD) has been mainly symptomatic. Small randomized or open-label case control studies of neurotransmitters have been inconclusive. We tried galantamine in the 2 most common varieties of FTD.

METHOD

Thirty-six behavioral variety FTD and primary progressive aphasia (PPA) patients were treated in an open-label period of 18 weeks and a randomized, placebo-controlled phase for 8 weeks with galantamine. The primary efficacy measures were the Frontal Behavioral Inventory, the Aphasia Quotient of the Western Aphasia Battery, the Clinical Global Impression of Severity and the Clinical Global Impression of Improvement.

RESULTS

No significant differences in behavior or language were found for the total group. A treatment effect (p = 0.009), in a subgroup of subjects with PPA in the global severity score, in favor of galantamine was detected in the placebo-controlled withdrawal phase but was not considered significant after correction for multiple comparisons. The language scores for the treated PPA group also remained stable compared to the placebo group, which showed deterioration.

CONCLUSION

Galantamine is not effective in the behavioral variety of FTD, but a trend of efficacy is shown in the aphasic subgroup, which may be clinically significant. Galantamine appeared safe in FTD/PPA.

Risperidone treatment of outpatients with schizophrenia: no evidence of sex differences in treatment response

OBJECTIVE

Given the renewed interest in the role of sex differences in schizophrenia, we undertook a post hoc analysis to determine whether sex differences in treatment response were present among outpatients with schizophrenia who received risperidone in an 8-week, open-label, Phase IV clinical study.

METHOD

We evaluated 330 adult patients (232 men, 98 women) with a DSM-III-R diagnosis of schizophrenia for safety and 292 (206 men, 86 women) for efficacy. Antipsychotic and antiparkinsonian medications were discontinued at study entry. Treatment with risperidone was initiated at a dosage of 2 mg daily, increased to the target dosage of 6 mg daily by day 3, and maintained at 6 mg daily until day 14. The dosage was then maintained at 6 mg daily, increased or decreased by 2 mg daily each week, based on the patient's response. Risperidone treatment was given for 8 weeks; the permitted dosage range was 4 mg to 10 mg daily.

RESULTS

Both male and female participants responded well to risperidone treatment; by the final assessment day, they had experienced decreases from baseline in their total Positive and Negative Syndrome Scale (PANSS) scores of 41.0% and 36.5%, respectively. Most male (77%) and female (78%) participants were considered to be PANSS responders: risperidone was effective against both the positive and negative symptoms of schizophrenia. Both sexes showed improvements over baseline in the incidence and severity of parkinsonism, dystonia, and dyskinesia. No significant (P > 0.05) sex differences in treatment response were observed for any of the efficacy outcomes or in the incidence and severity of extrapyramidal symptoms (EPS).

CONCLUSIONS

In this population of outpatients with chronic schizophrenia, both men and women responded well to flexible doses of risperidone. No significant sex differences were evident either in treatment response or in neurological side effects. The absence of sex differences in response to risperidone treatment may obviate the need for a sex-based differential dosing in schizophrenia management.

Parent and child mealtime behavior in families of children with cystic fibrosis

OBJECTIVES

We investigated the hypothesis that children with cystic fibrosis (CF) and their parents would show more maladaptive behaviors during dinner than children without CF and their parents.

STUDY DESIGN

Children with CF (n = 32) and their parents were compared with 29 children without CF and their parents on the rate and frequency of parent-child behaviors during a typical dinner in the families' homes by using multivariate analyses of variance.

RESULTS

When the rate of behavior, controlling for meal length, was examined, no differences were found between groups. However, parents of children with CF were found to differ from parents of control subjects in the frequency of direct and indirect commands (P <.05), coaxes (P <.01), physical prompts (P <.01), and feeding their child (P <.05). Children with CF were found to engage in more talk, spend more time away from the table, refuse food, and exhibit more noncompliance toward commands to eat than control children (P <.05 for all child variables). When behaviors were examined as a function of meal phase, parents of children with and without CF both showed an increase in commands (P <.01), coaxes (P <.05), feeds (P <.01), and physical prompts (P <.01) in the second half of the meal as compared with the first. Children with CF and the control children showed an increase in behaviors incompatible with eating during the second half of the meal compared with the first (P <.01). When faster eaters were compared with slower eaters, faster eaters consumed a higher percentage of the recommended daily allowance of energy (P <.01) than slower eaters and showed a trend to be at higher weight percentiles for age and sex (P =.08) regardless of group (CF or control).

CONCLUSIONS

Children with CF and their parents do not differ from children without CF and their parents in the rate of behaviors exhibited or types of strategies used to encourage eating. However, children with CF and their parents engage in these behaviors more frequently. Our data do not support typical parenting behaviors as effective in meeting the CF dietary requirements. Additional support in the form of child behavior management training may be needed to assist parents in meeting their child's caloric requirements.

Impact of microbiology practice on cumulative prevalence of respiratory tract bacteria in patients with cystic fibrosis

Investigators participating in the Epidemiologic Study of Cystic Fibrosis project began to collect microbiological, pulmonary, and nutritional data on cystic fibrosis (CF) patients at 180 North American sites in 1994. Part of this study was a survey undertaken in August 1995 to determine microbiology laboratory practices with regard to pulmonary specimens from CF patients. The survey included a section on test ordering, completed by a site clinician, and a section on test performance and reporting, completed by each site's clinical microbiology laboratory staff. Seventy-nine percent of the surveys were returned. There was intersite consistency of microbiology laboratory practices in most cases. The majority of sites follow most of the CF Foundation consensus conference recommendations. There were differences in the frequency at which specimens for culture were obtained, in the use of selective media for Staphylococcus aureus and Haemophilus influenzae, and in the use of a prolonged incubation for Burkholderia cepacia. These variations in practice contribute to prevalence differences among sites and may result in differences in clinical care.

Cystic fibrosis, nutrition, and the health care team

Because of the multiple systems involved in cystic fibrosis, the variability and chronicity of the disease, and the increased survival of this population, a specialty team of experts for care has evolved. A multidisciplinary approach is essential to assist patients and their families in adjusting to the disease and to optimize treatment interventions. The dietitian is responsible for assessment of nutritional status, including the determination of energy requirements and eating habits, interpretation of anthropometric data, and evaluation of nutritional adequacy. The nutrition care plan forms an integral part of the overall treatment objectives and is reported to other team members as it is devised, implemented, and monitored. A consensus report issued in April 1990 by the Cystic Fibrosis Foundation includes both general nutrition guidelines and detailed recommended treatment standards aimed at providing optimal nutrition care.

Descriptive analysis of eating behavior in school-age children with cystic fibrosis and healthy control children

STUDY OBJECTIVE

To investigate calorie intake, behavioral eating styles, and parent perception of eating behavior of school-age children with cystic fibrosis (CF) compared with healthy peers.

DESIGN

A two-group comparison study.

SETTING

A clinical sample of 28 school-age children with CF and a community sample of 28 healthy peers matched for age (6 to 12 years) and socioeconomic status.

MEASUREMENTS AND MAIN RESULTS

The children with CF consumed more calories per day (2175 cal/d) than the control children (1875 cal/d) and achieved a significantly higher recommended daily allowance (RDA) of energy (128% of the RDA) than the control children (91.61% of the RDA). Fifty-four percent of the CF sample were achieving the CF dietary recommendations of 120% of the RDA. Despite this energy intake, the CF sample was significantly below the control sample on weight (24.56 vs 31.23 kg), height (125.48 vs 133.06 cm), and z score for weight (-0.811 vs 0.528) and height (-0.797 vs 0.371). On measures of behavioral eating style, the CF sample had significantly longer meals (23.90 min) than the control sample (17.34 min) and had a significantly slower pace of eating (43.27% 10-second intervals with bites) than the control sample (51.29% 10-second intervals with bites) but did not differ significantly on the number of calories consumed during dinner. On a measure of parent report of mealtime behaviors, parents of the children with CF rated mealtime behavior problems of "dawdles" and "refuses food" as more intense (mean, 3. 46) than did the parents of control children (mean, 2.67). For the CF sample, a significant correlation was found between the parent intensity ratings of problem behavior in general and meal duration (r = .48), and a significant negative correlation was found between the parent intensity ratings of problem mealtime behaviors and the percentage of intervals with bites (pace of meal) (r = -.533).

CONCLUSIONS

Although the school-age children with CF were consuming more calories per day than their healthy peers, and more than 50% of the children in the CF sample were at or above the CF dietary recommendations, the children in the CF sample were significantly below the control children on measures of weight and height. The behavioral data suggest that increased caloric intake is not without cost, because the CF sample spent an additional 7 minutes per day at dinner and ate their meals at a slower pace than their healthy peers. These data were associated with higher intensity ratings of mealtime behaviors by parents of children with CF. These findings point to the need for individualized assessment of energy needs for school-age children with CF and comprehensive programs that teach parents behavioral strategies to motivate their children to meet these higher energy requirements in an adaptive manner.

Behavioral intervention to improve calorie intake of children with cystic fibrosis: treatment versus wait list control

Changes in calorie intake and weight gain were evaluated in five children with cystic fibrosis (CF) who received behavioral intervention and four children with CF who served as wait list controls. The behavioral intervention was a 6-week group treatment that provided nutritional education plus management strategies aimed at mealtime behaviors that parents find most problematic. The control group was identified prospectively and was evaluated on all dependent measures at the same points in time pre- and posttreatment as the intervention group. Difference scores on calorie intake and weight gain from pre- to posttreatment were compared between groups using t tests for independent samples. The behavioral intervention group increased their calorie intake by 1,032 calories per day, while the control group's intake increased only 244 calories per day from pre- to posttreatment [t(6) = 2.826, p = 0.03]. The intervention group also gained significantly more weight (1.7 kg) than the control group (0 kg) over the 6 weeks of treatment [t(7) = 2.588, p = 0.03] and demonstrated catchup growth for weight, as indicated by improved weight Z scores (-1.18 to -0.738). The control group showed a decline in weight Z scores over this same time period (-1.715 to -1.76). One month posttreatment, the intervention was replicated with two of the four children from the control group. Improved calorie intake and weight gain pre- to posttreatment were again found in these children. At 3- and 6-month follow-up study of children receiving intervention, maintenance of calorie intake and weight gain was confirmed. No changes were found on pulmonary functioning, resting energy expenditure, or activity level pre- to posttreatment. This form of early intervention appears to be promising in improving nutritional status and needs to be investigated over a longer period of time to evaluate the effects of treatment gains on the disease process.

Management of chronic sinusitis in cystic fibrosis

Chronic rhinosinusitis is extremely common in patients with cystic fibrosis. It causes numerous problems in these patients and can put them at risk for life-threatening illness. Potential problems include nasal obstruction, congestion, sinus pain and pressure, infection (usually with Pseudomonas organisms), hyposmia or anosmia, and the seeding of bacteria into the lower respiratory tract. Cystic fibrosis patients with chronically infected sinuses are at increased risk for pneumonia following lung transplantation. A prophylactic protocol has been developed for the management of chronic sinusitis in patients with cystic fibrosis. These patients are fully evaluated at the Nasal Dysfunction Clinic of the University of California, San Diego (UCSD), Medical Center. Based on the results of the evaluation, they are treated with endoscopic sinus surgery, partial middle turbinectomy, septoplasty, and a large middle meatal maxillary antrostomy. Surgery is followed by a rigorous regimen of pulsatile hypotonic saline nasal irrigation to wash away tenacious cystic secretions. Tobramycin (Nebcin) is given once daily in the nasal irrigant to inhibit the growth of Pseudomonas organisms. At the USCD Nasal Dysfunction Clinic, this prepulmonary transplantation protocol is now used in all cystic fibrosis patients with chronic sinusitis.

Oxidative metabolism in Rett syndrome: 1. Clinical studies

The etiology of Rett syndrome (RS) remains a mystery. The clinical phenotype has similarities to that of patients with mitochondrial defects of oxidative metabolism. There is evidence of lactate and pyruvate elevations in blood and CSF in some patients. Over the last 10 years we have studied girls with RS looking for evidence of a defect in oxidative metabolism. We present data on lactate and pyruvate blood measurements in 30 patients with RS with repeated measurements performed over time in many. Taken as a whole the means of measurements of lactate and pyruvate fall within the control range, however, individual patients have marked elevation of both lactate and pyruvate with considerable fluctuation over time. Nine girls with typical RS were studied in detail using a clinical protocol designed to identify disorders of oxidative metabolism. These patients underwent fasting for 24 hours, glucose loading and alanine loading tests. Seven girls had skin and muscle biopsies performed. One patient admitted with particularly high blood lactate levels underwent hourly blood collections over a 24 hour period during which state of alertness was noted and respiratory monitoring was performed. In this patient serial blood sampling for lactate performed. In this patient serial blood sampling for lactate performed with oxypneumocardiogram recording demonstrated a fall in plasma lactate to normal levels during sleep when the respiratory pattern was normal. Such fluctuations of plasma lactate apparently correlated with sleep/wake state and respiration suggest that in some patients with RS lactate elevations may arise from respiratory abnormalities. Other positive findings included prediabetic glucose responses in three girls. Ammonia levels following alanine loading were normal in all patients.

The possible use of coralline hydroxyapatite as a bone implant

Hydroxyapatite developed from sea coral has been utilized as a bone implant. The primary application at this time is in maxillofacial surgery along with experimental use in orthopedic surgery. The acceptance of this implant in bone and by the body has been found to be excellent without signs of rejection or increase in the incidence of infection. Advantages of this material over autogenous and allogenic bone grafts will be discussed along with its potential application to podiatric surgery.

Ganglions in the sinus tarsi

The contents of the sinus tarsi are reviewed along with an analysis of ganglions. The possibility of ganglions as a cause of sinus tarsi syndrome is supported by the case reports. The formation of ganglions in the sinus tarsi and their role in the etiology for this condition are emphasized.

The effect of various forms of immobilization on plantar foot pressure

In this study, 16 subjects wore different types of immobilization devices while peak pressures on the plantar aspect of the foot were measured using the Electrodynogram (E.D.G.) system. Objective and subjective data were generated and analyzed. Peak pressures decreased on the plantar aspect of the foot as the form of immobilization progressed up the leg.

The time course of metabolic changes induced by dietary cholesterol in guinea pigs

The time course of the effects of dietary cholesterol on the lipid composition of liver, plasma and red cells of guinea pigs, of the pathological changes of tissues and of hematological parameters was studied. The purpose was to identify the primary injury and so to contribute to the eludication of the mechanism(s) for the development of the hemolytic anemia observed in this species after long-term cholesterol supplementation. The results showed that the initial effects observed within 1 week occur in the liver lipids and histology accompanied by changes in plasma and RBC lipids. These events were followed by further, slower increases of tissue lipids without major qualitative changes. The earliest signs of an anemia were observed between weeks 5 and 7. We conclude that the primary insult of cholesterol is liver damage leading to the production of abnormal plasma lipoproteins which in turn cause a net increase of RBC-cholesterol that is accompanied by their morphological abnormalities. The hemolytic anemia does not seem to be caused directly by either the altered composition of RBC nor their altered morphology.

Cardiopulmonary responses to exercise in obese girls and young women

A study of exercise performance was carried out in 17 obese girls and young adults. During submaximal steady-state bicycle exercise oxygen intake (Vo2) for a given work output (W) was raised in obese subjects but minute ventilation at a fixed carbon dioxide output, gas exchange, blood gases, and cardiac output at a given VO2 were similar to the values previously found for normals. In obese subjects high levels of VO2 for fixed W were also obtained on the treadmill but when these were standardized for body weight (unlike the bicycle test) it was shown that the obese girls and women exercised within the normal (expected) range of aerobic energy expenditure. During maximal performance the absolute VO2 max was the same in obese and nonobese subjects but for a given body weight, lean body mass, and leg muscle (plus) bone volume, VO2max was reduced by 23.8, 16.3, and 24.5% respectively, in the former group. It was concluded that obesity though having minimal affect on responses to submaximal exercise is nevertheless associated with a marked reduction in physiological performance at or near maximal effort.