Development and evaluation of low-volume tests to detect and characterize antibodies to SARS-CoV-2

Low-volume antibody assays can be used to track SARS-CoV-2 infection rates in settings where active testing for virus is limited and remote sampling is optimal. We developed 12 ELISAs detecting total or antibody isotypes to SARS-CoV-2 nucleocapsid, spike protein or its receptor binding domain (RBD), 3 anti-RBD isotype specific luciferase immunoprecipitation system (LIPS) assays and a novel Spike-RBD bridging LIPS total-antibody assay. We utilized pre-pandemic (n=984) and confirmed/suspected recent COVID-19 sera taken pre-vaccination rollout in 2020 (n=269). Assays measuring total antibody discriminated best between pre-pandemic and COVID-19 sera and were selected for diagnostic evaluation. In the blind evaluation, two of these assays (Spike Pan ELISA and Spike-RBD Bridging LIPS assay) demonstrated >97% specificity and >92% sensitivity for samples from COVID-19 patients taken >21 days post symptom onset or PCR test. These assays offered better sensitivity for the detection of COVID-19 cases than a commercial assay which requires 100-fold larger serum volumes. This study demonstrates that low-volume in-house antibody assays can provide good diagnostic performance, and highlights the importance of using well-characterized samples and controls for all stages of assay development and evaluation. These cost-effective assays may be particularly useful for seroprevalence studies in low and middle-income countries.

Establishing breast feeding in infants with Down syndrome: the FADES cohort experience

OBJECTIVE

To describe breastfeeding prevalence and maternal experience in infants with trisomy 21.

DESIGN

Longitudinal cohort study.

SETTING

Participants from UK recruited through websites, social media and local collaborators: neonatologists, community paediatricians and research nurses.

SUBJECTS

Infants under the age of 8 months with Down syndrome (DS) recruited to the Feeding and Autoimmunity in Down Syndrome Evaluation Study between 1 September 2014 and 31 August 2017. Seventy participants: median age 20 weeks (IQR 13-29 weeks) at initial questionnaire.

MAIN OUTCOME MEASURE

Breastfeeding prevalence at 6 weeks and 6 months among infants with DS.

RESULTS

The prevalence of exclusive breast feeding among study participants was similar to the general population (13/61, 21% vs 23% at 6 weeks, 2/54, 4% vs 1% at 6 months). However, the prevalence of breast feeding (exclusive or combination feeding) among the study participants was higher than the general population (39/61 64% vs 55% at 6 weeks, 32/59 54% vs 34% at 6 months).

CONCLUSION

Although there may be challenges in establishing breast feeding in infants with DS, our data suggest that exclusive breast feeding is possible for some, and the prevalence of breast feeding is comparable to the prevalence in the general population.

TRIAL REGISTRATION NUMBER

ISRCTN12415856.

Maternal microchimerism in cord blood and risk of childhood-onset type 1 diabetes

BACKGROUND

Maternal microchimerism (MMc), the transmission of small quantities of maternal cells to the fetus, is relatively common and persistent. MMc has been detected with increased frequency in the circulation and pancreas of type 1 diabetes (T1D) patients. We investigated for the first time whether MMc levels at birth predict future T1D risk. We also tested whether cord blood MMc predicted MMc in samples taken at T1D diagnosis.

METHODS

Participants in the Norwegian Mother and Child Cohort study were human leukocyte antigen (HLA) class II typed to determine non-inherited, non-shared maternal alleles (NIMA). Droplet digital (dd) polymerase chain reaction (PCR) assays specific for common HLA class II NIMA (HLADQB1*03:01, *04:02, and *06:02/03) were developed and validated. MMc was estimated as maternal DNA quantity in the fetal circulation, by NIMA specific ddPCR, measured in cord blood DNA from 71 children who later developed T1D and 126 controls within the cohort.

RESULTS

We found detectable quantities of MMc in 34/71 future T1D cases (48%) and 53/126 controls (42%) (adjusted odds ratio [aOR] 1.27, 95% confidence interval (CI) 0.68-2.36), and no significant difference in ranks of MMc quantities between cases and controls (Mann-Whitney P = .46). There was a possible association in the NIMA HLA-DQB1*03:01 subgroup with later T1D (aOR 3.89, 95%CI 1.05-14.4). MMc in cord blood was not significantly associated with MMc at T1D diagnosis.

CONCLUSIONS

Our findings did not support the hypothesis that the degree of MMc in cord blood predict T1D risk. The potential subgroup association with T1D risk should be replicated in a larger cohort.

Merlin controls the repair capacity of Schwann cells after injury by regulating Hippo/YAP activity

The regenerative capacity of Schwann cells in the PNS underlies functional repair after injury. In this study, Mindos et al. show a new function for the tumor suppressor Merlin and Hippo/YAP signaling in the generation of repair-competent Schwann cells after injury.

Loss of the Merlin tumor suppressor and activation of the Hippo signaling pathway play major roles in the control of cell proliferation and tumorigenesis. We have identified completely novel roles for Merlin and the Hippo pathway effector Yes-associated protein (YAP) in the control of Schwann cell (SC) plasticity and peripheral nerve repair after injury. Injury to the peripheral nervous system (PNS) causes a dramatic shift in SC molecular phenotype and the generation of repair-competent SCs, which direct functional repair. We find that loss of Merlin in these cells causes a catastrophic failure of axonal regeneration and remyelination in the PNS. This effect is mediated by activation of YAP expression in Merlin-null SCs, and loss of YAP restores axonal regrowth and functional repair. This work identifies new mechanisms that control the regenerative potential of SCs and gives new insight into understanding the correct control of functional nerve repair in the PNS.

Pulmonary artery leiomyosarcoma: an unusual cause of shortness of breath

INTRODUCTION

Primary leiomyosarcomas of the pulmonary artery are very rare tumours with 30 cases reported in the English literature. Herein, we report the first case with evidence of a renal metastasis.

MATERIALS AND METHODS

The tumour was discovered at autopsy in a 61-year-old woman who had presented with shortness of breath and chest pain. It was located in the pulmonary trunk with extension into the adjacent pericardial cavity. Separate nodules were found in the pulmonary valve, the left pulmonary artery and the left kidney.

RESULTS

On microscopic examination, the tumour was composed of spindle cells with cigar-shaped nuclei immunoreactive for vimentin, desmin, CD68 and α-smooth muscle actin.

CONCLUSIONS

Primary pulmonary artery leiomyosarcoma is easily confused clinically with pulmonary thromboembolism and most cases are diagnosed post mortem. Most tumours arise in the pulmonary trunk and metastases are only rarely described. The management of patients with this rare tumour depends on early surgical resection and the prognosis is unfavourable.

Small cell neuroendocrine carcinoma of the breast: a report of three cases and review of the literature

Small cell neuroendocrine carcinoma of the breast is a rare tumour with less than 30 cases reported in the literature. The clinicopathological findings of three cases of primary neuroendocrine carcinoma of the breast and a review of the pertinent literature are presented. The morphological and immunohistochemical patterns of this tumour are similar to its pulmonary counterpart. Expression of neuroendocrine markers is inconsistent, so morphology is the mainstay of diagnosis. Size is a very important prognostic factor in this tumour, as in breast carcinomas of the usual type.

Aneursymal bone cyst of the proximal phalanx of the thumb in a child

Aneursymal Bone Cysts (ABCs) involving the hand are a rare occurrence. We report a case of an ABC of the proximal phalanx of the thumb in a boy which was treated successfully with curettage and autologous bone grafting. When the diagnosis of ABC of the small bones of the hand is entertained, prompt therapeutic intervention is indicated because of the potential for aggressive local behaviour. In the paediatric patient, simple surgery to preserve the growth plate is recommended.

Internal displacement in Burma

The internal displacement of populations in Burma is not a new phenomenon. Displacement is caused by numerous factors. Not all of it is due to outright violence, but much is a consequence of misguided social and economic development initiatives. Efforts to consolidate the state by assimilating populations in government-controlled areas by military authorities on the one hand, while brokering cease-fires with non-state actors on the other, has uprooted civilian populations throughout the country. Very few areas in which internally displaced persons (IDPs) are found are not facing social turmoil within a climate of impunity. Humanitarian access to IDP populations remains extremely problematic. While relatively little information has been collected, assistance has been focused on targeting accessible groups. International concern within Burma has couched the problems of displacement within general development modalities, while international attention along its borders has sought to contain displacement. With the exception of several recent initiatives, few approaches have gone beyond assistance and engaged in the prevention or protection of the displaced.

Australia's oldest human remains: age of the Lake Mungo 3 skeleton

We have carried out a comprehensive ESR and U-series dating study on the Lake Mungo 3 (LM3) human skeleton. The isotopic Th/U and Pa/U ratios indicate that some minor uranium mobilization may have occurred in the past. Taking such effects into account, the best age estimate for the human skeleton is obtained through the combination of U-series and ESR analyses yielding 62,000+/-6000 years. This age is in close agreement with OSL age estimates on the sediment into which the skeleton was buried of 61,000+/-2000 years. Furthermore, we obtained a U-series age of 81,000+/-21,000 years for the calcitic matrix that was precipitated on the bones after burial. All age results are considerably older than the previously assumed age of LM3 and demonstrate the necessity for directly dating hominid remains. We conclude that the Lake Mungo 3 burial documents the earliest known human presence on the Australian continent. The age implies that people who were skeletally within the range of the present Australian indigenous population colonized the continent during or before oxygen isotope stage 4 (57,000-71,000 years).

Papillary carcinoma in a thyroglossal duct remnant--a review of thyroglossal surgery in a regional centre in the west of Ireland

A review of thyroglossal duct remnants presenting to a regional centre in the West of Ireland was undertaken. Over a 15 yr period, 25 patients were operated on for duct remnants. The mean age was 19.6 yr and ranged from 3 to 68 yr. There were 16 (64 per cent) males and 9 (36 per cent) females. Seventeen (68 per cent) patients were less than 20 years at the time of surgery. Four patients presented with a sinus and the remainder with a cystic lesion. Two patients experienced recurrent disease. One patient, a 41 yr old female, had a papillary carcinoma of a thyroglossal cyst. There were no clinical features distinguishing this patient from those with benign cystic remnants of the thyroglossal duct. The possibility of carcinoma in older patients, in particular females, presenting with thyroglossal cysts emphasises the importance of performing a formal Sistrunk's operation. It reduces the risk of recurrence of the cyst and may reduce the risk of recurrence of the tumour as the duct may provide a route for the spread of tumour.

Massive thymic hemorrhage in a neonate: an entity revisited

The authors describe a case of early neonatal death of a full-term infant who had respiratory distress and anemia after fetal distress during labor. Postmortem examination disclosed mediastinal compression by a large fresh hemorrhage into the left lobe of the thymus. Massive thymic hemorrhage is an extremely rare but sometimes lethal occurrence; it may represent a manifestation of early-onset hemorrhagic disease of the newborn.

Clinical evaluation of near-continuous oral micronized progesterone therapy in estrogenized postmenopausal women

In an open non-comparative prospective trial of 12 months' duration, we investigated the role of a novel hormone replacement therapy regimen in 40 post-menopausal women who sought hormone replacement therapy. The regimen consisted of continuous administration of 0.625 mg of conjugated equine estrogen coupled with a fixed low-dose of micronized oral progesterone administered for 23 days every calendar month. The regimen was well-tolerated, producing no major side-effects and was effective in relieving menopausal symptoms. The study showed that 40% of the women experienced side-effects and 20% withdrew from the study. Half of the 20% of the women who dropped out did so for reasons not related to treatment. All symptomatic women experienced improvement after the 1st month, and virtually all were asymptomatic by the 3rd month of treatment, persisting until the end of the trial with the average number of hot flushes per day declining from the pretreatment levels by 96%. Amenorrhea was observed in 47% of patients, amenorrhea and minimal vaginal bleeding in 78% but acyclic bleeding was present in 28% of those in whom bleeding was re-established. Endometrial atrophy was induced in the majority of patients and no atypical endometrial hyperplasia was encountered. No significant changes were observed in blood glucose or liver enzymes. The mean percentage changes from baseline for serum cholesterol, triglycerides, high-density lipoprotein (HDL) cholesterol, low-density lipoproteins (LDL) and LDL/HDL ratio were -6%, +32% (p < 0.001), -16% (p < 0.05), +15% (p < 0.05) and -23% (p < 0.05), respectively. The regimen was clinically effective and its apparent lack of major side-effects, the protective effect on the endometrium, the added advantage of minimal vaginal bleeding and the beneficial effect on lipid/lipoprotein levels, offer an attractive therapy and improved compliance with postmenopausal hormone replacement therapy.

Unexplained stillbirths and sudden infant death syndrome

Comparison of necropsy records, clinical details and epidemiological data of 93 unexplained stillbirths and 149 cases of sudden infant death syndrome provides compelling evidence that these disorders represent a continuum of a single spectrum of disease. Regarding them as a single disease entity could lead to a clearer understanding of both.

Aberrant thyroglossal cyst

A case is presented of a laterally occurring thyroglossal cyst. In conventional teaching, thyroglossal duct remnants occupy the midline, or a position adjacent to the midline, and are found in a line marking the descent of the thyroid anlage and move upwards on protruding the tongue. Laterally presenting thyroglossal duct remnants are unusual.

Cell proliferation in breast tumours: analysis of histological parameters Ki67 and PCNA expression

Ki67 and Proliferating Cell Nuclear Antigen (PCNA) are antigens expressed in the nucleus during various phases of cell division, which can be detected immunohistochemically using monoclonal antibodies. Thirteen fibroadenomas and 39 carcinomas were examined for expression of Ki67 and PCNA. A staining index was calculated for each tumour as the percentage of positive cells in the areas of highest density. The mean index for both antibodies was significantly lower in fibroadenomas than in malignant tumours. A wide range of proliferation rates was seen in the malignant group; the mean Ki67 index of Grade I carcinomas was 9% +/- 4.4 (mean +/- SD), of Grade II 14.3 +/- 8.7 and of Grade III 26.2 +/- 15.7. These differences are statistically significant. In malignant tumours there was a good correlation between the mitotic count and the Ki67 index (r = 0.61, p < 0.005) but none between the mitotic count and PCNA index. There was a weak correlation between the Ki67 and the PCNA indices (r = 0.38 p < 0.005), but no correlation was found between either index and oestrogen receptor status, patient age or tumour size. Ki67 immunohistochemistry is a convenient method for assessing cell proliferation, applicable in most laboratories. The validity of measuring proliferation in this way has yet to be established but the wide variation of expression even within the conventional grading categories may help to discriminate prognostically distinct subgroups. Expression of PCNA appears to correlate poorly with Ki67 expression in breast tumours and not with mitotic count; therefore its usefulness as a marker of proliferative activity, on current evidence, appears to be limited.

Patterns of cytokeratin expression by neoplastic and non-neoplastic epithelium

Eighty-one epithelial lesions were studied immunohistologically for cytokeratin protein expression using three anticytokeratins CAM 5.2, NCL5D3 and RCK102. Consistent differences were noted between squamous and glandular neoplasms. Squamous and cutaneous carcinomas were found to preferentially express higher molecular weight cytokeratins than adenocarcinomas. In addition, tumours of similar morphology from different sites showed differences in expression of these markers. Differences in pattern were also found between benign and malignant lesions in the case of liver and urinary bladder. Thus the value of cytokeratin profile analysis in characterisation of epithelial neoplasms is confirmed and may be useful in distinguishing benign from malignant tumours in some instances.

Low-dose progesterone therapy in oestrogenised postmenopausal women: effects on plasma lipids, lipoproteins and liver function parameters

BACKGROUND

Cardiovascular disease among older women is a major health problem and is the leading cause of death in this group in developed countries. The risk is reduced in oestrogen users secondary to favourable lipid changes, but the beneficial effect of oestrogen may be counteracted when concomitant progestogens are administered.

OBJECTIVE

To study the effects of a novel hormone replacement therapy regimen on liver enzymes, lipids and lipoproteins in postmenopausal women.

DESIGN

Prospective open, non-comparative trial for 12 months.

METHODS

40 healthy postmenopausal women, (mean age +/- S.D.), 53.5 +/- 3 years received 0.625 mg of conjugated equine oestrogen daily and 100 mg of micronised oral progesterone (P) for the first 23 days every calendar month for 12 months without interruption.

MAIN OUTCOME MEASURE

Gonadotrophins, liver function parameters and lipoproteins were measured before treatment and at the 6th, 9th and 12th months of treatment.

RESULTS

Compliance with treatment was confirmed by a 33% decrease in mean serum level of follicle stimulating hormone at the end of 1 year of treatment. In the same period, the mean serum cholesterol, LDL and LDL/HDL ratio decreased by 6%, 16% and 23% of the base line levels, respectively. The percentage changes in triglycerides and HDL from the basal levels were +32% (P < 0.001) and +15% (P < 0.05), respectively.

CONCLUSION

These results indicate that near continuous administration of fixed low-dose of P has no adverse effects on the lipid milieu of postmenopausal women when combined with long-term continuous oestrogen replacement therapy provided women with borderline triglyceridaemia are excluded.

Acardius in a triplet pregnancy: cytogenetic and morphological profile

We describe a rare case of acardius in a triplet pregnancy terminated by Caesarean Section at 32 weeks gestation. Morphological and chromosomal abnormalities of the fetus as well as structural abnormalities of the placenta are presented. Cytogenetic analysis and examination of the single disc triplet placenta provide evidence for the two major theories of pathogenesis of acardius, the twin reversed arterial perfusion (TRAP) sequence and the genetic theory, which we believe are not necessarily mutually exclusive.

Stillbirths: a clinicopathological survey (1972-1982)

A survey of 325 stillbirths from 27,072 babies delivered at University College Hospital Galway from April 1, 1972 to March 31, 1982, gave a stillbirth rate of 12 per thousand, which, when corrected for 66 lethal congenital abnormalities, became 9.6 per thousand. The cause of death in each stillbirth was determined clinically and pathologically where possible and was classified according to a modified Aberdeen classification of perinatal death. Consideration of the birth weights of the babies who died showed that 223 (68.6%) weighed over 1,500 g, and excluding those with abnormalities, they must be considered salvageable with the application of intensive neonatal care. There were 54 (16.6%) intrapartum deaths, which must also be considered preventable. The application of ultrasonic surveillance should complement clinical acumen, by allowing easier detection of the fetus at risk, thereby facilitating earlier intervention which in turn should reduce antenatal stillbirths.

A clinical role for right ventricular endomyocardial biopsy

There is considerable uncertainty about the value of endomyocardial biopsy (EMB) in the diagnosis and management of patients with suspected primary myocardial dysfunction. To determine the clinical utility of this procedure in patients referred to our centre, we reviewed the clinical records and biopsy findings of the first 21 consecutive patients in whom we performed right ventricular EMB. Patients were divided into four groups according to the clinical indications for EMB: unexplained congestive cardiac failure and a dilated heart (Group 1: 11 patients); unexplained congestive cardiac failure and a non dilated heart (Group 2: three patients); unexplained cardiomegaly in the absence of cardiac failure (Group 3: one patient); suspected hypertrophic cardiomyopathy (HCM) (Group 4: six patients). Histological examination of EMB tissue obtained from all patients in Group 1 as well as the single patient in Group 3 showed non specific features judged to be compatible with a diagnosis of dilated cardiomyopathy. Accordingly, in all patients in Groups 1 and 3, a potentially treatable cause of primary myocardial dysfunction was excluded. Biopsy examination demonstrated the presence of a specific disease process in two of three patients in Group 2 (one patient had amyloidosis, the other endomyocardial fibrosis). In five of the six patients in Group 4, the biopsy findings were either diagnostic or suggestive of HCM. Our results suggest that EMB is a clinically useful tool in patients presenting with features suggestive of a primary myocardial disorder.

The distribution of pregnancy-associated prostaglandin synthetase inhibitor in the human placenta

The distribution of pregnancy-associated prostaglandin synthetase inhibitor (PAPSI) has been studied in 181 human placentae and early products of conception using a peroxidase-antiperoxidase (PAP) immunohistological method. PAPSI was detected in amniotic epithelium throughout all stages of gestation. Extravillous trophoblast was PAPSI-positive throughout gestation. Villous trophoblast was PAPSI-positive in the first 12 weeks of gestation, when PAPSI was localized to syncytiotrophoblast but not to cytotrophoblast. Villous syncytio- and cytotrophoblast were both PAPSI-negative from 12 weeks to term. Fetal and maternal polymorphs contained PAPSI at all stages of gestation, as did villous Hofbauer cells. The significance of these findings is discussed in relation to putative functions of PAPSI, particularly the maintenance of pregnancy and control of onset of parturition.

Perinatal mortality in multiple pregnancy patients

A study of perinatal mortality in multiple pregnancy over a period of 12 years, 1972 to 1984, showed prematurity and low birthweight as the major causes of fetal loss. The highest risk was found at 28 to 30 weeks gestation (306/1,000). There was a significantly greater risk to babies delivered by the breech (136/1,000), and likewise in the second twin when compared with the first, ratio 1:14. A significant drop in the perinatal mortality rate, from 98/1,000 to 39/1,000, was observed between 1972-1978 and 1979-1984. Ultrasound has facilitated the earlier diagnosis of twins and provides more accurate serial fetal assessment. Bedrest, more vigilant antenatal care, intrapartum surveillance and improved neonatal care, are required to maintain and further reduce the perinatal mortality rate. When regional analgesia was employed in labour, the number of babies lost was 41/1,000, vs 93/1,000 in patients not receiving regional analgesia. External cephalic version and vertex delivery of the second twin is preferable to internal version and breech extraction. It should also be contemplated, as an alternative to elective cesarean section for a transverse lie or breech presentation of the second fetus.

Zygosity and placental structure in monochorionic twins

To test the assumption that monochorionic twins are monozygotic, cord bloods from 12 sets of monochorionic twins were tested for a total of 16 red cell antigens. Discrepancies were noted among the minor blood groups in 3 of the 12 sets. The result of this pilot study strengthens the contention of others who have previously questioned the general acceptance that monochorionicity and monozygosity are synonymous.

The Neu-Laxova syndrome in female sibs: clinical and pathological features with prenatal diagnosis in the second sib

We report on affected sisters with the Neu-Laxova syndrome. Prenatal diagnosis of the condition was achieved by serial ultrasound examinations which demonstrated abnormal fetal growth in the second affected fetus before 24 weeks gestation.

Pathologic findings in fetal GM1 gangliosidosis

A 24-week fetus with GM1 gangliosidosis (type 1) was studied using biochemical and histopathologic methods. Foam cells in viscera and placenta demonstrated widespread accumulation of a lipidlike material. By microscopy, central nervous system storage appeared confined to the retina and dorsal root ganglia, but the brain ganglioside content was measurably elevated compared with that of age-matched controls. These data, along with those of others, imply that, if the observed pathologic findings are irreversible, any attempts at intrauterine therapy must commence prior to the middle of the second trimester.

A pilot study of the frequency and significance of placental villitis

The prevalence of inflammatory villous lesions was determined in a prospective study of 120 consecutive placentas. Cord blood IgM level was measured as an indicator of fetal intrauterine infection, and the birthweights of the infants were noted. Ten cases of villitis were found. Two infants had elevated cord blood IgM and one of them also had amniotic infection. As only one case of villitis had corroborative evidence of transplacental intrauterine infection, 90% of the lesions require an alternative explanation. The severity of the lesions correlated with the presence of low birthweight. The quality of the inflammatory infiltrate was also considered. Only one case included plasma cells; the remainder showed lymphohistiocytic infiltration. The case with plasmacytic infiltration was the one with elevated cord blood IgM. It is concluded that placental villitis is usually not an infective condition and its aetiology remains unknown.

A role for amniotic epithelium in control of human parturition

A peroxidase anti-peroxidase staining technique was used to determine the presence of pregnancy-associated prostaglandin synthetase inhibitor (PAPSI) in human amniotic epithelium from 20 pregnant women at 36-40 weeks' gestation. PAPSI was present in amniotic epithelial cells in 12 of 15 women before the onset of labour. No PAPSI was found in amniotic epithelium from 5 women in clinically established labour. These findings indicate that the amnion is a source of this endogenous prostaglandin synthetase inhibitor and suggest a local role for amniotic epithelium in initiating labour at term.

Fraser syndrome presenting as monozygotic twins with bilateral renal agenesis

Fraser syndrome without cryptophthalmos is described in monozygotic twins concordant for bilateral renal agenesis.

Conduction system defects in three perinatal patients with arrhythmia

The cardiac conduction systems of three patients who died in the perinatal period were studied histologically. Rhythm disturbances were observed in these patients immediately before death. The sinus node was notably hypoplastic without increase in fibrous content in all cases. The atrioventricular node was smaller than expected in all, and the entire atrioventricular conduction axis was small in two cases. This study supports the need for a detailed examination of the cardiac conduction system so as to provide a better understanding of the clinicoanatomical relation in the context of fatal perinatal arrhythmias.

Patterns of Refsum's disease. Phytanic acid oxidase deficiency

Four children each exhibiting a profound deficiency of phytanic acid oxidase activity in cultured skin fibroblasts but with very different phenotypes, are described. A consistently raised plasma phytanic acid value, generally considered to be pathognomonic for Refsum's disease (phytanic acid oxidase deficiency), was observed in three of these children but not in the fourth, who also showed no evidence of accumulation of phytanic acid in liver or fat biopsies. Our data suggest that the clinical diagnosis of Refsum's disease in children is more difficult because the full spectrum of clinical features usually observed in adults with the disorder is not always present. Moreover, a failure to detect a raised plasma phytanic acid value may not necessarily indicate normal fibroblast phytanic acid oxidase activity.

Concordant monozygotic twins with bilateral renal agenesis

We report the unique observation of monozygotic twins concordant for bilateral renal agenesis.

Recurring digital fibroma

Seven cases of recurring digital fibroma were seen over a 35-year period. All demonstrated the classical clinical, macroscopic, and microscopic features of this distinct tumour, including the pathognomonic round, eosinophilic cytoplasmic inclusion bodies. Ultrastructurally, all seven cases were confirmed to be myofibroblastic in nature, and the morphology and intracellular topography of the inclusion bodies suggested their derivation from contractile protein. These findings establish recurring digital fibroma as a neoplastic lesion of the myofibroblast.

Hyperplastic parathyroiditis--a new autoimmune disease?

A case of parathyroiditis with epithelial hyperplasia is reported in which the histological features suggest an autoimmune process analogous to Hashimoto's disease.

Serum acid phosphatase activities in patients with lung cancer: a biochemical and immunohistochemical analysis of 25 cases

A series of 25 cases of lung cancer are presented in which total (TAcP) and nonprostatic serum acid phosphatase (NPAcP) activities were measured. Of these cases, 36% had raised TAcP and NPAcP activities in their serum. However, the serum activities of TAcP and NPAcP did not correlate with either the presence of lung cancer nor with the morphological tumour type. This fact indicates that, despite isolated reports of raised serum acid phosphatase activities in cases of lung cancer, acid phosphatase is of no value as a marker for lung cancer. We sought alternative explanations for the raised TAcP and NPAcP activities observed in our series in the hope that this enzyme might prove useful as a marker for early metastatic disease in lung cancer patients. This possibility is not substantiated, and the findings are analyzed and discussed. It is tentatively suggested that raised NPAcP activities in patients with lung cancer may relate to haemostasis.