Mark Corson

By J. Milten. Minot State University--Bottineau.

One day later discount 250mg chloromycetin visa, he developed a fever and was being neutropenia and mucosal barrier damage started on ticarcillin-clavulinate and gentamicin discount chloromycetin 250 mg without prescription. Patients whose major defect is suppression of cell- the next 48 hours discount 500mg chloromycetin visa, he remained febrile, and he devel- mediated immunity resulting from the administra- oped a black skin lesion (2 2 cm) on his right thigh. Four of four blood cultures drawn It is absolutely essential that these distinctions be at the onset of fever were positive for Pseudomonas made at the initial patient encounter, because important aeruginosa, Escherichia coli, and Klebsiella pneumo- decisions about diagnostic approaches and the need niae. His antibiotic regimen was switched to cef- for immediate empiric therapy and its type have to be tazidime and gentamicin. Some defects are tem- Neutropenia is dened as an absolute neutrophil count below 500/mm3. It is often accompanied by porary, until repair mechanisms return to full function- ality (for example, the bone marrow recovers, mucosal mucosal damage. Gram- positive pathogens have increased in frequency in a) associated with corticosteroids, and recent series describing neutropenic bacteremia, b) follow immunosuppression for organ trans- probably as a consequence of the increased use of plantation. The mally, any bacteria passing through the mucosa are most frequently encountered organisms are E. However, bacteremia with serious infection is considerably higher when the anaerobes is occasionally seen in association with neutrophil count is less than 200/mm3. The incidence of infections is low if human or environmental flora that infect the Table 16. Sources of Bacteria Commonly Infecting Neutropenic Patients Skin Oral cavity Gut Coagulase negative staphylococci Streptococcus viridans Escherichia coli Staphylococcus aureus Oral anaerobes Klebsiella spp. Organisms that are present cause severe infections in other populations Mucor in lower numbers and that are resistant to antibac- species, for example are only infrequently encoun- terial agents for example, yeasts and moulds tered in the neutropenic patient. However, it should be borne in mind that certain fungi are held in check by Pathogens Encountered in Patients with cell-mediated immunity, and these pathogens Suppression of T Cell Functions infect patients with compromised cell-mediated The number of patients with suppression of T cell func- immunity. Initially, patients receiv- Fungal infections usually develop after broad-spectrum ing corticosteroids were the major group of patients antibiotics have had time to reduce the competing bac- falling into this category. In patients with no prior history of fungal connective tissue disease including lupus erythematosus infection, these pathogens are not usually seen for at and rheumatoid arthritis are being treated with new least 7 days into a febrile neutropenic episode. These fungal infections are often called superinfections, agents also impair cell-mediated immunity. Most of the because they occur while patients are receiving antibac- patients in this category have undergone organ trans- terial agents. Occasionally, when a patient has received antibiotics Post-transplant infections fall into two groups: in the recent past and the level of fungal colonization in the gut is high, fungi may emerge as primary Infections occurring during the rst postoperative pathogens early in neutropenia before antibiotics are month. Fungi that may period include Legionella species and other gram-neg- appear early in neutropenia include Candida species ative bacilli such as P. During the rst month, transplant patients are also About Infections Associated with at risk of developing infections transmitted by the Neutropenia and Mucositis donor organ or organs. Risk is inversely related to the number of neu- cocci) or gram-negative bacteremia before death. Still, bacteria can occasionally survive in a among those found on the skin and in the oral vascular aneurysm or other protected sites. Bacteria include Staphylococcus epidermidis, that becomes apparent only when the organ is trans- Staph. Immunosuppression is at its highest during this period to prevent acute rejection. Atypical mycobac- acquired from blood transfusion or transplantation with teria may become more invasive and cause symptomatic an infected organ. However, the virus actively replicates in mon fungal pathogen encountered in the transplant 20% to 30% of transplant recipients and can cause a population. Depending on geographic location, About Infections in Patients with Defective Histoplasma capsulatum and Coccidioides immitis are also Cell-Mediated Immunity important pathogens in these patients. Increasingly, the dematiaceous ( black ) fungi are being reported as a cause of infections. Can contract the same community-acquired causes infection in this population, probably because pathogens as normal hosts. Have an increased risk of bacterial infections The role of lamentous fungal infections in organ with Mycobacterium species, Listeria monocyto- transplantation cannot be overemphasized. Fungal infections are often life-threatening and continued immunosuppression, and death is a common may be difcult to diagnose. In most instances, cell-mediated and humoral considered depending on geographic location. Reactivation of old viral infections is a major against many viruses, unless total ablation of existing T concern. Can be usually contain memory cells to make antibody, but the the result of reactivation, blood transfusion, or transplantation with an infected organ. Transplant patients therefore tend to be more susceptible to viruses that are latent in b) Epstein Barr virus is less common. Other possible pathogens include Pneumocys- of cell-mediated immunity allows latent viruses to reac- tis, Toxoplasma, disseminated Strongyloides. Three phases of immunosuppression follow in severe, hypoxic pneumonia in transplant patients. Patients mediated and humoral immunity,chronic graft- with low level Strongyloides infection can develop dis- versus-host disease seminated strongyloidiasis in association with 2.

There was considerable overlap in mea- surements between those scalps graded as dandruff and those without but an increase in the rate of cell production was suggested quality 250mg chloromycetin. Turnover time was measured by observing the disappearance of the dye from the scalp buy chloromycetin 500 mg free shipping. As expected purchase chloromycetin 500mg visa, the disappearance from the psoriasis scalps was rapid (5 days), but the mean number of days to disappearance from the dandruff (12. In the same study, fresh scalp biopsy specimens were incubated with tritiated thymidine and the incorporation into the basal layer of the epidermis recorded. Again, the results with the dandruff and non-dan- druff scalps were nearly equal while the incorporation into psoriatic cells was almost four- fold greater. The current understanding of dandruff is that while some degree of increased cell turnover may contribute to the amount of aking, this is not a primary hyperproliferative condition. Effec- tive treatment occurs with a wide variety of active ingredients that have in common their antifungal activity rather than cytostatic effects. Dandruff and Seborrheic Dermatitis: Use of Medicated Shampoos 79 Nature of Flaking Individually shed corneocytes from the scalp surface are too small (approx. It is only when they are shed as aggregates that they are large enough to be appreci- ated as dandruff akes. Transmission electron microscopy of scalp tape strips has been reported by Warner et al. Many of the corneocytes were separated by a thick mass of sebum-like intercellular lipid. Even areas of the dandruff subjects scalps with less obvious aking still showed similar ultra- structure pathology but tape strips from the lower leg of a subject with severe dandruff were normal. Treatment with zinc pyrithione shampoo effected improvement in the visible dandruff which directly correlated with normalization of the stratum corneum ndings. The reduced or absent desmosomes in dandruff scalp samples are in contrast to the ndings in dry skin of the legs (winter xerosis), where reduced degradation of corneodesmosomes and their abnormal retention in the supercial layers of xerotic stratum corneum underlie reduced desquamation (68,69). The safety, cosmetic acceptability, and ease of use are of concern since these are chronic condi- tions requiring long-term treatment. Teresi, in Lost Discoveries: the Ancient Roots of Modern Science From the Babylonians to the Maya (70), reports that the ancient Egyptians con- cocted potions using hippopotamus fat to control dandruff. Efcacy Testing Methods Most clinical trials to establish efcacy of antidandruff and anti-seborrheic dermatitis products rely on direct observation of scalp scale (72 74). Typically, test subjects use a standardized non- treatment shampoo for at least two weeks to achieve a baseline state. Further standardization is achieved by specifying an interval, for instance three days, between the last wash-out shampoo use and the clinical grading. The scalp is evaluated by sectioning and parting the hair to visualize the entire scalp. The amount of observed aking is graded visually in multiple sections of the scalp, commonly using a 0 10 or 0 4 rating scale. The evalua- tion of adherent scalp aking is more reproducible than evaluation of loose scale, as loose akes vary with hair texture and recent scratching, brushing or combing more than adherent scale. Scalp grading is then repeated after use of the products to be tested, commonly at inter- vals of 2, 4, and 6 weeks. While visual grading is at best semi-quantitative, a trained and experienced grader will demonstrate consistency in duplicate grading tests and reproducible results in clinical trials. Subjective data from subject questioning about pruritus or cosmetic qualities of a product may also be collected. Long-term use studies for safety and efcacy are performed with subjects using a product frequently (5 10 times per week) over weeks or months of observation. Other measures of dandruff severity such as tape stripping or counting corneocytes col- lected from scrubbing small areas of the scalp with solvents are useful for physiology studies but not practical for routine efcacy demonstration. These techniques have the inherent disad- vantage of assessing only a small portion of the scalp surface (75). Food and Drug Administration Monograph on Drug Products for the Control of Dan- druff, Seborrheic Dermatitis, and Psoriasis (77) lists the following active ingredients as gener- ally recognized as safe and effective for over-the-counter human use. Keratolytics Salicylic acid is still used as it was over one hundred years ago for dandruff. When using a kera- tolytic shampoo, the patient should allow the lather to stand on the scalp for a few minutes to facilitate loosening of the scale. Oils such as peanut oil or olive oil applied to the scalp under occlusion with a shower cap can soften scale and facilitate removal. Residual oily products such as pomades left on the scalp promote the growth of Malassezia and aggravate the condition. Patients should be warned against vigorous scratching since electron microscopy conrms hair shaft damage from excoriation. Antipruritics By reducing the Malassezia-driven inammation of dandruff and seborrheic dermatitis, most effective antimicrobial shampoos are expected to also reduce scalp itch. Anti-Malassezia Agents The majority of effective treatment shampoos have in common their activity against Malassezia yeast. In general, their antidandruff effect parallels their antimicrobial potency (81 83). Coal Tar Coal tar s antifungal effect has been demonstrated in vitro against Malassezia strains isolated from dandruff, seborrheic dermatitis, and pityriasis versicolor (84). While it is a weak antifungal, tar has additional antiproliferative (85) and anti-inammatory effects making it a rst-line choice Dandruff and Seborrheic Dermatitis: Use of Medicated Shampoos 81 for psoriatic scalp treatment.

Formulation and application techniques are likely to strongly inuence the contribution of direct impaction to overall mortality buy 250 mg chloromycetin overnight delivery. Secondary pick-up Residual infection can also make a signicant contribution to overall mortality cheap 500mg chloromycetin with visa. In eld experiments proven chloromycetin 250 mg, 40 50% of the total infection of the grasshopper Hieroglyphus daganensis Krauss resulted from residual infection. Residual infection is inuenced by initial infectivity, persistence (Thomas et al. However, it should be considered that emulsiable adjuvant oils may cause conidia to be too strongly bound to hair, limiting availability to transfer to the target. Alternatively, conidia too loosely bound may become easily dislodged by movement of animals or rainfall. Dillon and Charnley (1985) demonstrated that pre-soaking can reduce the time to germination of conidia. Further study is required to determine if pre-soaking can improve pathogenicity in ticks. Prolonging eld persistence of the conidia may improve the performance of the fungus in the eld as there is a higher probability of the target encountering the entomopathogen (Inglis et al. There are few studies that have attempted to measure persistence of applied entomopathogens on cattle. This suggests that time which conidia can persist on cattle may be relatively short and may limit residual infection. Several factors which either encourage death or germination of conidia may inuence persistence of conidia. These laboratory results were not replicated in the eld where persistence was much greater, presumably because many conidia were shielded from direct sunlight, perhaps by their location on the vegetation. Little is known about the tolerance of an entomopathogen to sunlight on the insect body, as it is assumed that penetration occurs within 24 h in most insects (Inglis et al. Secondary cycling Secondary cycling is unlikely to contribute to overall infection on the cattle surface as infected ticks are likely to detach from the cattle host and fall off the animal. However, increasing the amount of fungal inoculum in the natural environment through secondary cycling, akin to pasture application, is likely to increase the levels of infection in the tick population. Conclusion and recommendations Based on the constraints identied, detailed recommendations for research are listed in Table 3. Myco-acaricides are likely to become a necessary tool considering the rate at which resistance is developing to existing products, the high cost of developing new chemical acaricides and the projected expansion of the geographic range of African tick species. This paper reviews the current status of control of cattle ticks by topical application of myco-acaricides, but in general, lays the foundation for the development of myco-insec- ticides for application to animal systems to control ectoparasites. There are numerous studies which demonstrate that entomopathogenic fungi are pathogenic to ticks but few which are useful for the development of an effective system for control based on myco- acaricides. This is similar to the position with the control of crop pests less than 20 years ago hence lessons can be drawn from recent studies which recognise that improvements in a succession of components are required to move successfully from isolating a fungus, to the development of a viable myco-insecticide. There is considerable potential for a myco-acaricide developed for pasture or topical application to cattle for the control of ticks. Experiments with pasture application have had excellent results while trials with topical application to cattle have been variable. Focus on evaluating isolates of are the key pathogens of ticks Metarhizium and Beauveria for tick and have very good safety pathogenicity. Host specicity of isolate An isolate with a broad Although narrow ecological host range physiological host range does isolates may have limited impacts on not necessarily mean the non-targets, a broad host range isolate ecological host range will be may be used to target a wider range of similarly wide. Determination of the ecological host range of isolates should only be a priority at later stages of research. Origin of isolate Contrary to a common belief, Limit focus on bioprospecting for isolates from tick species have isolates from ticks and screen isolates not proven to be more from international collections with pathogenic to ticks than non- good production characteristics for tick isolates. Virulence In bioassays, high concentrations Identify highly virulent tick pathogenic of conidia are generally isolates and calculate minimum lethal required to produce mortality doses for all tick stages. Sublethal effects can affect reproduction in ticks and could be used in control strategies. Host factors Tick species A range of tick species are Identify a suite of isolates which are susceptible to pathogenic to a wider range of entomopathogenic fungi. Development stage All developmental stages are Identify a suite of isolates which are susceptible to pathogenic to mature and immature entomopathogenic fungi but stages and test if formulation can single isolates may vary in improve range. Anatomy Ticks, particularly non-engorged Determine if the anatomy of ticks makes stages, may provide a greater the use of myco-acaricides impractical challenge to fungal for the control of certain tick species. Diseases of Mites and Ticks 141 Table 3 continued Inuencing factors Key ndings/possible impacts Recommendations for research Life cycle One-host ticks spend most of Determine how long various tick species their life cycle attached to a are on cattle and determine single host and are easy to appropriate application strategy for target using topical myco-acaricides. The development stages of three-host ticks spend the majority of their time off host, making topical applications of myco-acaricide less effective. Location Tick species have specialised Determine where tick species reside on habitats on animal host. Host skin microenvironment Skin temperature Efciency of entomopathogenic Identify high temperature tolerant fungi is generally reduced at isolates, either those which can grow mammalian skin temperatures. Coat humidity Humidity of the skin surface is Conduct further studies on humidity in relatively low and may not the cattle coat and its effect on provide moisture necessary for germination of conidia. It is of promising isolates Identify lower unclear if pH of the relevant pH tolerant strains of range has major impacts on entomopathogenic fungi.

Health advisers also encounter a significant number of patients with mental health problems or borderline mental health issues that present in crisis buy cheap chloromycetin 500mg online, even though they might not have psychiatric histories order chloromycetin 500 mg overnight delivery. It is important to understand that reactions to crisis are normal discount chloromycetin 250mg line, but that sometimes they can be resolved in dysfunctional ways. This can lead to post-traumatic stress disorder, for example, in vulnerable individuals. Caplan was the first to define crisis in psychosocial terms as being: when a person faces an obstacle to important life goals that is, for a time, insurmountable through the utilisation of customary methods of problem solving. A period of disorganisation ensues, a period of upset, during which many abortive 11 attempts at solution are made. Prompt 13 treatment was elsewhere reported to be effective in keeping soldiers at the front. One-off interventions have since been shown to be useful in many areas, for example in reduced self- 14 harming behaviour. Following 500 deaths in a Boston fire he looked at the effects of bereavement follow-up, and found that the duration, severity and resolution of the crisis was affected by timely crisis intervention. Indeed he coined the term grief work and promoted a view that human behaviour in an acute crisis was not abnormal or pathological. The normative developmental and existential crises that confront all people at some time may 16 17 be acutely activated (or interfered with) as a result of trauma. Indeed many of the patients that health advisers engage in productive work are in one kind of crisis or another. The Greek derivation of the word points to it being seen as a decision-making turning point. The Chinese pictogram for crisis combines two others representing danger and opportunity. Roberts saw crisis as: a temporary state of upset and disequilibrium characterised chiefly by an individual s inability to cope with a particular situation using existing methods of 18 problem solving, and by the potential for a positive of negative outcome. Then 24 to 48 hours later, emotional collapse, then some adjustment (functional or dysfunctional) days to weeks later. Caplan emphasised that crisis is self-limiting (usually lasting 4-6 weeks and therefore determining the length of therapeutic contract). The outcome depends on the availability of appropriate help together with individual and environmental factors. The importance of early intervention on outcome is highly significant for health advisers. Referring on the patient in crisis too soon may be more likely to result in a dysfunctional adjustment, and more mental health problems later. Other theorists have produced models that lend themselves to crisis intervention approaches. Interestingly these are also models which have developed at least in part as a response to the 22 need for crisis intervention work. Features of a crisis intervention approach 24 A useful overview of the field makes the following statements about crisis intervention work: It is essential that the therapist views the work being done not as a second best approach but as the treatment of choice for an individual Accurate and rapid assessment of the presenting problem and underlying factors is more important than a lengthy diagnostic evaluation It should be kept in mind that the treatment is sharply time-limited (one to six sessions) and the therapist should persistently direct their energies to the resolution of the presenting problem and work in a here and now way It follows that time must not be wasted dealing with irrelevant material The therapist must be willing to take an active and sometimes directive role 112 Maximum flexibility of approach is encouraged: the therapist may need to be a resource co-ordinator or information giver The therapeutic goal is explicit and directed to helping the individual to regain at least their pre-crisis level of functioning Methodology It is important to take a view of the adult survivor s behaviour as an understandable rather than pathological reaction to stress, and assuming an active and directive role overall strategy to increase the individual s remobilisation and return to functioning. A seven-stage model for crisis intervention is described: Assessing lethality and safety needs - is the patient suicidal or in danger? It is recommended that health advisers make their treatment and referral decisions with reference to this key document. The type of counselling undertaken This is usually dictated by patient need, the training and experience of the health adviser, and the counselling supervision available to the health adviser. Where contracted counselling is indicated, the patient would be referred elsewhere for assessment: to an appropriate relevant health adviser or other counsellor, internally or outside the immediate clinical setting. Where a health adviser is undergoing counselling training and would like to develop their patient work/ patient hours then they may be able to negotiate to have one longer term patient (for example for a six month contract). The caseload It is not good practice for a full time health adviser to see more than 5 counselling patients per week or more than 3 if part-time. Service needs may necessitate a lower limit, and the size of caseload needs to be discussed with the senior health adviser. Preventing role confusion Sometimes there is a difficulty when a patient is being seen for counselling who simultaneously requires a different type of input. Referring on There are some patients where it may be more appropriate that they are referred to another agency or professional within the multidisciplinary team (for example clinical psychologist, counsellor, psychiatrist or social worker). At no time should a health adviser risk their own personal safety Sometimes it may be more appropriate for a colleague to work with a particular patient. In this situation an assessment with that colleague would be arranged (with their permission). Often the patient will have engaged with the health adviser, as the first person they have discussed their problem with, and an important therapeutic attachment may be broken at a critical phase. The worker or agency being referred to may have less experience and training in the critical area of sexual health than the person doing the referring. Also, trainees largely staff counselling agencies, and sometimes there are lengthy waiting times. Documentation As a minimum it is important to document in the medical notes for each session that a patient has been seen, and what the number of the session is. In the interest of making the work more inclusive to others from the multidisciplinary team then (whatever system is adopted) any counselling notes need to be regarded as confidential to the clinic and need to contain an overview of the session including any medical implications or medico-legal concerns. There needs to be an explicit focus for the work, and recording of partner notification issues and risk reduction work. The Data Protection Act makes no distinction between formal and informal notes, so any additional notes (for example for supervision) must be kept at least as securely as the medical notes. At the end of the agreed contract of sessions the health adviser will write a closure letter or summary and put this in the medical notes.