Superiority of systemic bleomycin to intradermal HOCl for the study of interstitial lung disease

Systemic sclerosis (SSc) is an autoimmune disease characterized by vasculopathy, immune dysregulation, and multi-organ fibrosis. Interstitial lung disease (ILD) is a complication of SSc and a leading cause of SSc-death. The administration of hypochlorous acid (HOCl) intradermally in the mouse (HOCl-SSc) purportedly shows several features typical of SSc. We studied the model by injecting BALB/c mice daily intradermally with HOCl for 6-weeks, an exposure reported to induce lung fibrosis. On day 42, the skinfold thickness and the dermal thickness were two and three times larger respectively in the HOCl group compared to controls. HOCl treatment did not result in histological features of pulmonary fibrosis nor significant changes in lung compliance. Automated image analysis of HOCl mice lungs stained with picrosirius red did not show increased collagen deposition. HOCl injections did not increase pulmonary mRNA expression of pro-fibrotic genes nor induced the production of serum advanced oxidation protein products and anti-topoisomerase 1 antibodies. Immune cells in bronchoalveolar lavage fluid (BALF) and whole lung digests were not increased in HOCl-treated animals. Since lung fibrosis is proposed to be triggered by oxidative stress, we injected HOCl to Nrf2-/- mice, a mouse deficient in many antioxidant proteins. Lung compliance, histology, and BALF leukocyte numbers were comparable between Nrf2-/- mice and wild-type controls. We conclude that the HOCl-SSc model does not manifest SSc-lung disease.

An unusually indolent well-differentiated Wilson-Jones angiosarcoma: A case report

Cutaneous angiosarcomas are rare soft tissue tumours originating from hematogenous vasculature that are aggressive and carry a poor prognosis. We describe the case of a 73-year-old man with a low-grade well-differentiated angiosarcoma. Our case distinguishes itself from those previously reported in the slow progression and important delay to the presentation of 30 months and survival time of 5.5 years. Additionally, its severe clinical appearance (T2 stage) but milder pathological picture (T1 stage) is very uncommon. A repeat biopsy is warranted when results are inconclusive and there is a high clinical suspicion of angiosarcoma.

Necrosis reduction efficacy of subdermal biomaterial mediated oxygen delivery in ischemic skin flaps

Inadequate tissue blood supply as may be found in a wound or a poorly vascularised graft, can result in tissue ischemia and necrosis. As revascularization is a slow process relative to the proliferation of bacteria and the onset of tissue necrosis, extensive tissue damage and loss can occur before healing is underway. Necrosis can develop rapidly, and treatment options are limited such that loss of tissue following necrosis onset is considered unavoidable and irreversible. Oxygen delivery from biomaterials exploiting aqueous decomposition of peroxy-compounds has shown some potential in overcoming the supply limitations by creating oxygen concentration gradients higher than can be attained physiologically or by air saturated solutions. We sought to test whether subdermal oxygen delivery from a material composite that was buffered and contained a catalyst, to reduce hydrogen peroxide release, could ameliorate necrosis in a 9 × 2 cm flap in a rat model that reliably underwent 40 % necrosis if untreated. Blood flow in this flap reduced from near normal to essentially zero, along its 9 cm length and subdermal perforator vessel anastomosis was physically prevented by placement of a polymer sheet. In the middle, low blood flow region of the flap, treatment significantly reduced necrosis based on measurements from photographs and histological micrographs. No change was observed in blood vessel density but significant differences in HIF1-α, inducible nitric oxide synthase and liver arginase were observed with oxygen delivery.

Spatially mapping the immune landscape of melanoma using imaging mass cytometry

Melanoma is an immunogenic cancer with a high response rate to immune checkpoint inhibitors (ICIs). It harbors a high mutation burden compared with other cancers and, as a result, has abundant tumor-infiltrating lymphocytes (TILs) within its microenvironment. However, understanding the complex interplay between the stroma, tumor cells, and distinct TIL subsets remains a substantial challenge in immune oncology. To properly study this interplay, quantifying spatial relationships of multiple cell types within the tumor microenvironment is crucial. To address this, we used cytometry time-of-flight (CyTOF) imaging mass cytometry (IMC) to simultaneously quantify the expression of 35 protein markers, characterizing the microenvironment of 5 benign nevi and 67 melanomas. We profiled more than 220,000 individual cells to identify melanoma, lymphocyte subsets, macrophage/monocyte, and stromal cell populations, allowing for in-depth spatial quantification of the melanoma microenvironment. We found that within pretreatment melanomas, the abundance of proliferating antigen-experienced cytotoxic T cells (CD8⁺CD45RO⁺Ki67⁺) and the proximity of antigen-experienced cytotoxic T cells to melanoma cells were associated with positive response to ICIs. Our study highlights the potential of multiplexed single-cell technology to quantify spatial cell-cell interactions within the tumor microenvironment to understand immune therapy responses.

Rare case of primary cutaneous adenoid cystic carcinoma of the abdomen: A case report

Adenoid cystic carcinoma is predominantly a tumor of the parotid glands and can sometimes be found in other glands. In most cases, skin location is usually a metastatic presentation and rarely a primary tumor. We describe the case of a 59-year-old female patient presenting with a 5-mm skin-colored nodule on the abdomen histologically compatible with a primary cutaneous adenoid cystic carcinoma. Extensive workup revealed no other primary source, nor evidence of metastatic disease; therefore, wide local excision was the preferred treatment given the low potential of recurrence. As this adnexal carcinoma is rare and its morphology non-specific clinically, we wanted to raise awareness of this entity and its management.

Verrucous plane xanthomas secondary to lipoprotein X dyslipidemia in the context of cholestatic fulminant hepatitis: A case report

Cutaneous xanthomas are the result of dermal deposition of lipid, mostly caused by disorders of lipid metabolism. Less commonly, they occur in the setting of cholestatic liver disease, leading to accumulation of lipoprotein X, a rare form of dyslipidemia that does not respond well to conventional treatments. We describe an atypical presentation of sudden diffuse xanthomas secondary to lipoprotein X dyslipidemia in the context of cholestatic fulminant hepatitis caused by trimethoprim-sulfamethoxazole hypersensitivity. Histopathology was also atypical and showed an unusual verrucous appearance consisting of overlying epidermal hyperplasia with hyperkeratosis. Our patient had significant improvement, after normalization of her lipid panel under cholestyramine and 13 sessions of apheresis, with topical corticosteroids offering some relief. This rare case shows the importance of recognizing atypical presentations of xanthomas, particularly when they do not respond to conventional dyslipidemia treatments.

Ischemia Regulates Endoglin Expression in a Pig Skin Flap Model

Endoglin is a transmembrane protein that binds transforming growth factor b (TGF-b) with high affinity. It is thought to modulate TGF-b signaling and responses through interactions on cell surfaces with TGF-b receptors. It is highly expressed on endothelial cells of tissues undergoing angiogenesis. Since ischemia-induced changes such as angiogenesis are in part regulated by TGF-b, it is important to elucidate the precise mechanism by which they occur if we are to influence the effects of ischemia on tissue. Since endoglin is one of the receptors involved in regulating TGF-b signaling, we tested whether endoglin expression will increase in response to ischemic injury. A pig skin flap model was developed and used in our laboratory to study the effect of ischemia on the expression of endoglin and its ligand TGF-b1 using immunohistochemistry. We observed an increased expression of endoglin and TGF-b1 in the epidermal layer, blood vessels, and fibroblasts in ischemic skin flaps as compared to non-ischemic control skin flaps. Given the role of TGF-b and endoglin in angiogenesis, this may represent a mechanism by which ischemia stimulates angiogenesis. Much work remains to be done to delineate the exact mechanisms by which TGF-b acts and the exact role of endoglin in TGF-b signaling. Understanding how to regulate the actions of TGF-b by manipulating the expression of endoglin may provide a therapeutic avenue given the importance of TGF-b in tumour angiogenesis.

A case of toxic epidermal necrosis-like cutaneous eruption as the first manifestation and clue to the diagnosis of systemic lupus erythematosus: A case report

We present a rare case of a 61-year-old woman presenting with a widespread erosive eruption on her torso and extremities. Although the lesions were histologically compatible with toxic epidermal necrolysis, clinically the patient was hemodynamically stable, had no mucosal involvement and had no relevant medical history or potentially incriminating medications. Further investigations uncovered a new diagnosis of systemic lupus erythematosus, with this toxic epidermal necrolysis-like eruption being the first presentation of the disease. This case highlights the importance of broadening the differential diagnosis in patients presenting with acute widespread cleavage of the epidermis, using the spectrum of acute syndrome of apoptotic pan-epidermolysis as a reference.

Multi-omic analysis reveals significantly mutated genes and DDX3X as a sex-specific tumor suppressor in cutaneous melanoma

The high background tumor mutation burden in cutaneous melanoma limits the ability to identify significantly mutated genes (SMGs) that drive this cancer. To address this, we performed a mutation significance study of over 1,000 melanoma exomes, combined with a multi-omic analysis of 470 cases from The Cancer Genome Atlas. We discovered several SMGs with co-occurring loss-of-heterozygosity and loss-of-function mutations, including PBRM1, PLXNC1 and PRKAR1A, which encodes a protein kinase A holoenzyme subunit. Deconvolution of bulk tumor transcriptomes into cancer, immune and stromal components revealed a melanoma-intrinsic oxidative phosphorylation signature associated with protein kinase A pathway alterations. We also identified SMGs on the X chromosome, including the RNA helicase DDX3X, whose loss-of-function mutations were exclusively observed in males. Finally, we found that tumor mutation burden and immune infiltration contain complementary information on survival of patients with melanoma. In summary, our multi-omic analysis provides insights into melanoma etiology and supports contribution of specific mutations to the sex bias observed in this cancer.

Pachyonychia Congenita (K16) with Unusual Features and Good Response to Acitretin

BACKGROUND

Pachyonychia congenita (PC) is a rare autosomal dominant disease whose main clinical features include hypertrophic onychodystrophy and palmoplantar keratoderma. The new classification is based on genetic variants with mutations in keratin KRT6A, KRT6B, KRT6C, KRT16, KRT17, and an unknown mutation. Here, we present a case of PC with unusual clinical and histological features and a favorable response to oral acitretin.

CASE

A 49-year-old male presented with diffuse and striate palmoplantar keratoderma, thickened nails, knuckle pads, and pseudoainhum. Histology showed compact hyperkeratosis, prominent irregular acanthosis, and extensive epidermolytic hyperkeratosis, suggestive of Vörner's palmoplantar keratoderma. However, keratin 9 and 1 were not mutated, and full exome sequencing showed heterozygous missense mutation in type I keratin K16.

CONCLUSION

To our knowledge, epidermolytic hyperkeratosis has not been previously described with PC. Our patient had an excellent response, maintained over the last 5 years, to a low dose of acitretin. We wish to emphasize the crucial role of whole exome sequencing in establishing the correct diagnosis.

An atypical case of bullous systemic lupus erythematosus in a 16-year-old boy

Bullous systemic lupus erythematosus (BSLE) is a rare autoimmune subepidermal blistering disease with a female predominance characterized as an acute vesicobullous eruption in patients with systemic lupus erythematosus (SLE). Here we report a case of BSLE in a 16-year-old boy that does not adhere to the criteria originally established and suggest a new outlook on this condition.

The effects of topical collagen treatment on wound breaking strength and scar cosmesis in rats

BACKGROUND

Topical application of collagen has been suggested to enhance wound healing; however, its long-term effect on wounds has not been studied in a rat model.

HYPOTHESIS

Topical application of collagen type I will not facilitate incision healing or cosmesis in rats up to 28 days postwounding.

METHODS

The effects of bovine collagen type I (6 mg/mL) on the rat surgical paired skin incision model were examined. Each rat served as its own control in which topical collagen was applied to one incision while normal saline (0.9%) was applied to the other incision. Rats were euthanized three (n=6), seven (n=6) and 28 (n=5) days after wounding. Tissue harvested from each time point was examined for maximal breaking strength, and for biochemical and histological analysis.

RESULTS

There were no statistically significant differences (ie, P<0.05) in maximum wound breaking strength between the collagen- and saline-treated wounds at all time points. Histological analysis revealed a similar infiltration of inflammatory cells and fibroblasts in the wound edges of all incisions when matched with time of wounding. Western blot analysis revealed no differences in fibronectin or collagen I content in all wounds in each rat.

CONCLUSIONS

The topical application of collagen did not facilitate wound healing from three to 28 days in the rat wound model.

Diagnosis and management of eosinophilic cellulitis (Wells' syndrome): A case series and literature review

INTRODUCTION

Eosinophilic cellulitis (Wells' syndrome) is an inflammatory dermatitis that is often misdiagnosed as infectious cellulitis due to its similarity in presentation. Misdiagnosis leads to delay of correct treatment and inappropriate use of antibiotics.

METHODS

A case series of eosinophilic cellulitis and a literature review are presented.

RESULTS

Patients with Wells' syndrome may present with a variety of nonspecific symptoms, such as fever, arthralgia and malaise, as well as myriad cutaneous lesions with associated erythema, presenting as blisters, bullae, papules and/or nodules. Several treatment modalities have been used to treat eosinophilic cellulitis and have been met with variable success rates; these include systemic corticosteroids, topical corticosteroids and antihistamines, with success rates of 91.7%, 50% and 25%, respectively.

CONCLUSIONS

A high degree of clinical suspicion must be exercised to diagnose this rare condition. Cellulitis with an atypical presentation or not responding to appropriate antibiotic treatment should trigger suspicion of Wells' syndrome. To date, the most successful treatment method is a short course of systemic corticosteroids.

Topical application of complement C3 in collagen formulation increases early wound healing

BACKGROUND

The complement system is composed of bactericidal and hemolytic proteins that increase capillary leakage and inflammatory cell migration. The role of complement C3 to augment wound healing has not yet been studied.

METHODS

We examined the effects of topical complement C3 formulation at two concentrations (10 and 100 nM) on the rat surgical skin incision model. Skin was examined for maximal breaking strength and sectioned for histological examination. Fibronectin and collagen I content were measured using western blot analysis.

RESULTS

There was a statistically significant 74% increase in maximum wound strength with the topical application of 100 nM of C3 at day 3 (850 ± 138 g) when compared to the control rats (490 ± 57 g). Histological correlation was seen with an increased inflammatory cell and fibroblast infiltration in treated wounds as compared to control rats as early as 3 days post-wounding. Western blots revealed increased fibronectin and collagen I levels in C3 treated wounds.

CONCLUSIONS

Topical application of complement C3 in collagen formulation to skin wounds significantly increases wound healing as early as 3 days after wounding. This is correlated with increased inflammatory cell recruitment and the subsequent early fibroblast migration and increased collagen deposition and organization in wounds.

Detection of 16 gamma-ray pulsars through blind frequency searches using the Fermi LAT

Pulsars are rapidly rotating, highly magnetized neutron stars emitting radiation across the electromagnetic spectrum. Although there are more than 1800 known radio pulsars, until recently only seven were observed to pulse in gamma rays, and these were all discovered at other wavelengths. The Fermi Large Area Telescope (LAT) makes it possible to pinpoint neutron stars through their gamma-ray pulsations. We report the detection of 16 gamma-ray pulsars in blind frequency searches using the LAT. Most of these pulsars are coincident with previously unidentified gamma-ray sources, and many are associated with supernova remnants. Direct detection of gamma-ray pulsars enables studies of emission mechanisms, population statistics, and the energetics of pulsar wind nebulae and supernova remnants.

The Fermi Gamma-Ray Space Telescope discovers the pulsar in the young galactic supernova remnant CTA 1

Energetic young pulsars and expanding blast waves [supernova remnants (SNRs)] are the most visible remains after massive stars, ending their lives, explode in core-collapse supernovae. The Fermi Gamma-Ray Space Telescope has unveiled a radio quiet pulsar located near the center of the compact synchrotron nebula inside the supernova remnant CTA 1. The pulsar, discovered through its gamma-ray pulsations, has a period of 316.86 milliseconds and a period derivative of 3.614 x 10(-13) seconds per second. Its characteristic age of 10(4) years is comparable to that estimated for the SNR. We speculate that most unidentified Galactic gamma-ray sources associated with star-forming regions and SNRs are such young pulsars.

Penetrating air gun wound in the neck

BACKGROUND

Injuries from air weapons can be serious and potentially fatal. It has been estimated that up to four million such weapons exist in UK households.

CASE REPORT

We present the case of an 8-year-old boy who sustained a penetrating neck wound from an air gun. Use of the flexible laryngoscope in the resuscitation room allowed localization of the gun pellet in the airway.

CONCLUSIONS

This approach, combined with careful clinical assessment led to immediate removal by direct laryngoscopy, thus avoiding the morbidity of unnecessary surgical exploration.

The significance and impact of a faculty teaching award: disparate perceptions of department chairs and award recipients

Teaching awards are commonly regarded as an incentive to encourage pedagogic excellence. Inasmuch as their effectiveness depends on how they are perceived by faculty, the authors investigated the impact of a teaching award in the Faculty of Medicine (Faculty Honor List for Educational Excellence) on the attitudes of award recipients and departmental chairs. A questionnaire was designed to sample opinion on the extent to which the Honor List program was publicized, whether the award contributed to recognition and/or stature in the academic unit, and whether it was personally valued by recipients. The questionnaire was sent to all 23 departmental chairs and to all 43 faculty members who had received the award between 1998 and 2002; 78% of the chairs and 77% of the recipients responded. The results revealed marked discrepancies between the perceptions of chairs and recipients. Chairs, although uncertain of the effect on quality of teaching, largely regarded the award as prestigious and well publicized within their departments. A notably smaller percentage of award recipients shared these views. Nonetheless, 93% of recipients valued the award highly, and 45% of recipients indicated that the award inspired them to enhance the quality of their teaching.

Cost and morbidity of MRSA in head and neck cancer patients: what are the consequences?

Methicillin resistant Staphylococcus aureus (MRSA) has become a prevalent nosocomial pathogen worldwide. The objectives of this study were to assess the morbidity and cost associated with the treatment of head and neck cancer patients who become colonized or infected with MRSA following major surgical procedures. We present a retrospective review of patients who underwent major surgery for head and neck cancer over a one year period and who then became MRSA positive in the post-operative period. MRSA affected 25/55 (45 per cent) patients who underwent major head and neck procedures during the period studied. The mean time of diagnosis was 13 days post-surgery. Morbidity included cellulitis, osteomyelitis and MRSA pneumonia. Thirteen of the patients who became MRSA positive (52 per cent of the MRSA group) required further surgery including plate removal, new flap formation and wound debridement as a result of the infection. Average in-hospital stay was almost three times more prolonged for patients who became MRSA positive compared to those who did not have MRSA. The costs of the first hospital stay were over three times more in the MRSA-positive group of patients. Antibiotic costs were increased by pound 2470 per patient because of MRSA. The extra stay in hospital, together with extra days in intensive care, extra medical and nursing care and additional costly antibiotic treatment, led to major cost implications and loss of health service resources in the unit. MRSA infection is a serious cause of morbidity in any surgical group of patients and this study focuses on the consequences for treatment of head and neck cancer patients in particular.

Management of a large bronchial haemangioma in an infant

Haemangiomas are the most common soft tissue tumor of infancy. Despite the benign and trivial nature of most cutaneous haemangiomas, airway haemangiomas are rare but potentially life threatening. We report the case of a 9-week-old infant with a left main stem bronchial haemangioma. This was successfully treated with the oral corticosteroids. We discuss the current available treatments for haemangiomas and highlight that treatment should be specific to each individual case.

Translevator anal anomalies with cutaneous fistulae passing deep to the scrotum

METHODS

The authors present a series of 9 patients collected from 4 centers with translevator anal anomalies, each of which has a fistula tracking forward deep to the scrotum and opening at the peno-scrotal junction. Whereas some would appear to be covered ani in type, others are deeper and would appear to fit in with an intermediate type of classification emphasizing the idea of a "spectrum" of malformation.

RESULTS

The anatomic arrangement, associated anomalies (eg, 2 had hypospadias), and surgical management is described briefly in each case. Careful examination may be necessary to identify the fistula.

CONCLUSIONS

It is recommended that the surgery be individualized depending on the findings. On a theoretical embryologic basis there is abnormality in the formation of the outer genital folds, and there also may be abnormality in some cases of the inner genital folds.

Reduction of glycemic and lipid levels in db/db diabetic mice by psyllium plant fiber

The soluble plant fiber psyllium significantly reduced fasting glucose and total cholesterol levels in the C57BL/KsJ db/db diabetic mouse relative to placebo-fed mice. Insulin levels were significantly higher in psyllium-fed than placebo-fed animals, indicating this fiber may delay the progression of diabetes in the animal model. High-density lipoprotein cholesterol levels rose moderately in both psyllium- and placebo-fed animals during the study, whereas triglyceride levels remained unchanged in both groups. Psyllium's effect on glycemic, lipid, and hormone parameters was not explained by weight loss or reduced food intake; these were similar in psyllium- and placebo-fed animals during the study. Our results show that psyllium fiber can beneficially moderate glycemic and lipid parameters in the db/db diabetes model.

Congenital leukonychia striata

Leukonychia striata of a unique appearance and distribution is described in a 51-year-old woman. Histopathologic examination of a specimen from the nail plate revealed a transverse band of parakeratosis on the ventral surface. Disturbance in keratinization on the nail plate is presumed to be secondary to abnormalities in the nail matrix. We review briefly the classification and pathogenesis of leukonychia, an interesting aberration in nail plate keratinization.

Clinical trial of cefuroxime axetil in children

Cefuroxime axetil tablets were given to 12 children (aged 19 months to 13.5 years) for a total of 14 episodes of lower respiratory tract infection. Doses ranged from 15 to 32 mg/kg/day. Six infections were regarded as cured and seven improved. In four cases, Haemophilus influenzae was present at the end of treatment. Serum levels of cefuroxime showed great variability. Absorption and penetration of the drug into the lower respiratory mucosa may not be sufficient to kill organisms which are sensitive in vitro. Cefuroxime axetil tablets were acceptable to most children.

Pigmentation induced by quinidine therapy

Abnormalities of pigmentation are a well-known side effect of antimalarial therapy. Quinidine, an antiarrhythmic agent, is structurally related to the common antimalarials but, to our knowledge, has not been associated with pigmentary abnormalities. We report a case of localized blue-gray pigmentation, clinically and histologically identical to antimalarial-induced pigmentation, in a patient receiving quinidine therapy.

Manipulation of platelet aggregation by prostaglandins and their fatty acid precursors: pharmacological basis for a therapeutic approach

Addition of the one-, two- or three- series endoperoxide to human platelet-rich plasma tend to suppress aggregation, through the action of their respective non-enzymatic breakdown products PGE1, PGD2, or PGD3 all of which elevate cyclic AMP levels. On the other hand, these stable primary products do not arise in appreciable amounts from intrinsic endoperoxides generated from either endogenous or exogenous free fatty acids. 5,8,11,14,17-Eicosapentaenoic acid (EPA) suppresses arachidonic acid (5,8,11,14-eicosatetraenoic acid) conversion by cyclooxygenase (as well as lipoxygenase) to aggregatory metabolites in platelets. Exogenously added EPA was capable of inhibiting PRP aggregation induced either by exogenous or endogenous (released by ADP or collagen) arachidonate. The hypothetical combination of an EPA-rich diet and a thromboxane synthetase inhibitor might abolish production of the pro-aggregatory species, thromboxane A2, and enhance formation of the anti-aggregatory metabolite, prostacyclin. Whereas EPA is not detectably metabolized by platelets, dihomo-gamma-linolenic acid (8,11,14-eicosatrienoic acid) is primarily converted by cyclooxygenase and thromboxane synthetase into the inactive metabolite, 12-hydroxyheptadecadienoic (HHD) acid. Pretreatment of human platelet suspensions with the thromboxane synthetase inhibitor imidazole unmasks the aggregatory property of PGH1 and DLL which was partially compromised by the PGE1 formed. The combination of the thromboxane synthetase inhibitor and an adenylate cyclase inhibitor unmasks a complete irreversible aggregation by DLL or PGH1. The basis of a dietary strategy that replaces AA with DLL must rely on the production by the platelet of an inactive metabolite (HHD) rather than thromboxane A2.

Vitamin C metabolism and atopic allergy

The procedure for carrying out the Leucocyte Ascorbic Acid Uptake Direct Antigen Challenge Test (LAADACT) is described. Leucocytes from normal individuals, when incubated in a buffered medium containing ascorbic acid, increase their ascorbic acid concentration by about 80%. When leucocytes from atopic individuals are incubated in a medium containing the antigen to which they are sensitive, as shown by positive skin tests, the leucocyte uptake of ascorbic acid is significantly reduced. Addition of antigen, to which atopic or normal individuals are not sensitive, to the incubation mixture does not reduce leucocyte ascorbic acid uptake. Measurement of ascorbic acid uptake into leucocytes is a relatively simple, routine, laboratory procedure. The LAADACT, therefore, provides a quick and accurate blood test for diagnosing sensitivity to specific antigens, and measuring relative antigenic sensitivities. The underlying mechanism of the LAADACT is discussed.