Natural killer (NK) cells are associated with reduced relapse without increased graft-versus-host disease (GVHD) after allogeneic hematopoetic stem-cell transplantation (HSCT)

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Background: Natural killer cells have potential for anti-leukemia activity after haplo-identical HSCT. However, the role of reconstituted NK cells in relapse and survival after matched HLA-identical HSCT is unknown. We investigated the correlation between NK reconstitution and death, relapse, and GVHD after HSCT. Methods: We prospectively studied NK reconstitution in 123 patients with predominantly high-risk hematologic malignancies. Peripheral blood absolute NK cell count (ANK) was determined by flow cytometry analysis of lymphocytes co-expressing bright staining CD56+ and CD16+. Cluster analysis distinguished patients at engraftment with high ANK (>12.2/mm3) (n=80) and low ANK (n=43), and at 60 days with high ANK (>20/mm3) (n=64) and low ANK (n=26). Primary study endpoints were death, relapse and acute grade II-IV GVHD with median follow up of 360 days (28–1967). A cox proportional hazard model was adjusted for important covariates, including age, transplant conditioning (myeloablative vs. non-myeloablative), graft source (peripheral blood vs. bone marrow), and donor-type (HLA-matched related vs. unrelated), dendritic cell level and absolute neutrophil count. Results: A low ANK at engraftment was significantly associated with death (p=0.03) after non-myeloablative HSCT. Using a selection model, only NK remained in the model, and a low ANK was associated with a 2.5 hazard ratio for subsequent death (p=0.04). Additionally, for the overall cohort, ANK at 60 days was strongly associated with time to death (92% in high vs 65% in low group; LR p=0.0007), at 310 days after HSCT. ANK level at 60 days was strongly associated with time to relapse (n=82, (LR p=0.0001). In a multivariate model, low ANK at 60 days was associated with a 4.2 fold relative risk (RR) of death (1.9, 9.1) and 8.6 RR for time to relapse (3.1, 24.3). Conclusions: High NK cell reconstitution is associated with reduced relapse and death without increased incidence of GVHD after HLA-identical HSCT. Our study suggests that NK may have both a potential anti-tumor effect, as well as be tolerogenic. Measuring NK after HSCT may have novel prognostic and therapeutic implications.

No significant financial relationships to disclose.

Dendritic cell (DC) reconstitution is associated with less opportunistic infections (OI) after allogeneic hematopoetic stem-cell transplantation (HSCT)

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Background: Dendritic cells are key antigen presenting cells which coordinate immune responses against infections. We investigated the correlation between DC reconstitution after HSCT and the onset of OI. Methods: We prospectively studied immune reconstitution of DC in 124 patients with predominantly high-risk hematopoetic malignancies. Peripheral blood underwent flow cytometry analysis for DC, defined as lineage negative, HLA-DR+, CD11c+ and CD123+. Cluster analysis demonstrated patients at engraftment with high DC (>6.92/mm3) (n =68), low DC (n=56), and at 60 days with high DC (>3.95/mm3) (n=48), and low DC (n=43). Primary study endpoint was onset of OI, defined as viral and invasive fungal (proven and probable) OI within 6 months of HSCT. A cox proportional hazard multivariate model was adjusted for important covariates, including age, transplant conditioning (myeloablative vs. non-myeloablative), graft source (peripheral blood vs. bone marrow), donor-type (HLA-matched related vs. unrelated), and ANC. Results: Patients with low DC at engraftment had significantly increased onset of acute grade II-IV GVHD by Kaplan-Meier analysis (p=0.004). Patients with onset of GVHD prior to day 60 were less likely to have high DC (32% with GVHD, 72% without GVHD) (p=0.001). Furthermore, low DC at 60 days was adversely associated with: time to viral OI (p=0.04), time to composite of viral OI and death (p=0.02), time to viral or fungal OI (p=0.009), and time to composite of viral or fungal OI and death (p=0.02). In the Cox model, low DC at 60 days, was associated with a 3.7 relative risk (RR) (1.2, 11.8) for onset of OI. Patients with onset of OI prior to day 60 were significantly less likely to have high DC (41% with OI, 61% without OI) (p=0.05). Conclusions: This study emphasizes the clinical importance of measuring DC after transplant. Patients with low DC reconstitution are at an increased risk of OI and death. Measuring DC, and further understanding of the likely complex factors involved in DC reconstitution, may provide rationale towards future therapeutic immune interventions.

No significant financial relationships to disclose.

The development of cytomegalovirus-induced adrenal failure in a patient with AIDS while receiving corticosteroid therapy

We report a case of Addisonian crisis due to cytomegalovirus (CMV) adrenalitis occurring in a patient with AIDS while receiving supraphysiological doses of steroids for the treatment of Pneumocystis carinii pneumonia. The case highlights the importance of considering the diagnosis of adrenal failure in AIDS, even in patients receiving supraphysiological doses of steroids.

Influenza-like episodes in HIV-positive patients: the role of viral and 'atypical' infections

OBJECTIVES

To document viral and 'atypical' infections in HIV-positive patients and association with influenza-like symptoms.

PATIENTS AND METHODS

Monthly culture of urine, faeces and throat swabs in 63 HIV-positive patients (30 asymptomatic and 33 with AIDS-related complex/AIDS) over 5-27 months (with 1125 patient-months of follow-up), with further sample collections during influenza-like episodes. Standard viral detection methods were used. Throat swabs were assessed for Chlamydia sp. by culture and immunoblotting, and for Mycoplasma pneumoniae by polymerase chain reaction.

RESULTS

Viruses were detected in 15 (50%) and M. pneumoniae in nine (30%) out of 30 HIV-positive patients during an influenza-like illness. A close temporal relationship with symptoms was observed in 12 (40%) patients: cytomegalovirus in six (20%), M. pneumoniae in three (10%), herpes simplex virus in three (10%), and enterovirus in one (4%). Influenza-like symptoms were more frequent in asymptomatic HIV infection than in AIDS-related complex/AIDS patients (actuarial risk at 1 year, 63 versus 26%; P=0.002), particularly in those with CD4 cell counts >300 x 10(6)/l at enrolment (P=0.002). At least 44% (four out of nine) M. pneumoniae infections were asymptomatic and 78% (seven out of nine) were associated with prolonged excretion (2-17 months). Chlamydia sp. were not detected.

CONCLUSIONS

Influenza-like symptoms were more likely to be reported by HIV-positive patients at early stages of disease, possibly as a result of differences in immune responses to viral infection. There was a close association in 40% of cases between the development of symptoms and detection of cytomegalovirus, herpes simplex virus, enterovirus and M. pneumoniae (a previously unrecognized association).

Epidemiology and molecular characterisation of toxigenic Corynebacterium diphtheriae var mitis from a case of cutaneous diphtheria in Manchester

Diphtheria is now an uncommon disease in Britain. We describe an imported case of cutaneous diphtheria in a previously immunised adult cause by C. diphtheriae var mitis. The control measures adopted to deal with the index case and two secondary cases so as to limit further spread among household and school contacts are outlined. Molecular typing was used to study the mode of spread of the organism among contacts.

Recurrent meningococcal septicaemia and properdin deficiency

A 32-year-old male presented with two episodes of meningococcal septicaemia, each of which was caused by a different serogroup of Neisseria meningitidis. Examination of the alternative pathway of complement revealed the rare X-linked disorder properdin deficiency (PD). Meningococcal Infection in complement deficiency states is discussed and the unusual features of this case are highlighted.

Stevens-Johnson syndrome following astemizole therapy

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Outcome of an exercise to notify patients treated by an obstetrician/gynaecologist infected with HIV-1

Experience with hepatitis B suggests that the risk of HIV transmission from a health care worker infected with HIV to a patient will be greatest during major surgical procedures. The number of patients worldwide who are known to have undergone such procedures, been notified, and subsequently tested is still too small to be confident that the risk of HIV transmission in these circumstances is negligible. We describe a patient notification exercise, undertaken in the United Kingdom in 1991. Attempts were made to contact 1217 patients, in three health districts (A, B, and C), who had undergone surgical procedures performed by an obstetrician/gynaecologist who was infected with HIV. The exercise aimed to offer the patients reassurance, counselling and--if they wished--HIV testing. One thousand one hundred and forty-two patients (94%) were contacted, and all 520 who elected to be tested were negative for anti-HIV. The proportion of identified patients tested was 63% in district A, 35% in district B, and 61% in district C. Surgical procedures were classified retrospectively according to the likely risk (none, possible, or high) of exposure to the doctor's blood and, therefore, risk of HIV transmission. One hundred and ninety-five of those tested had undergone a procedure that carried a high risk of exposure; 179 had undergone a procedure thought to carry no risk. Patients in districts A and C who had undergone a procedure that carried a high risk of exposure were more likely to be tested than those who had not; 206 patients overall had undergone procedures that carried a high risk of exposure but were not subsequently tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy and effects on pulmonary function tests of weekly 600 mg aerosol pentamidine as prophylaxis againstPneumocystis carinii pneumonia

A prospective study was designed to evaluate the efficacy and effects on pulmonary function tests of weekly 600 mg aerosolised pentamidine as prophylaxis against Pneumocystis carinii pneumonia (PCP) amongst two groups of patients infected with the human immunodeficiency virus. Group 1 (primary prophylaxis) consisted of patients with either diseases indicative of AIDS other than PCP or whose absolute CD4 positive lymphocyte count was below 200/mm3, and Group 2 (secondary prophylaxis) comprised patients with previous proven episodes of PCP. Fifty-five patients (30-Group 1, 25-Group 2) were studied over a period of 36 months, and no patients reached a study end point of either relapse or death due to PCP after a mean duration of treatment of 14.9 months (range 9-36 months). There were no significant differences between the pulmonary function tests (forced expiratory volume in the first second, forced vital capacity and carbon monoxide diffusion capacity) performed at the start and end of the study on both groups of surviving patients. Ten patients (18%) reported coughing and eight patients (15%) were documented to have bronchoconstriction, which was found to be preventable by prior administration of disodiumcromoglycate. The results showed that weekly 600 mg aerosolised pentamidine is effective and well tolerated for primary and secondary prophylaxis against PCP without additional adverse effects. Further prospective randomized trials are needed to determine whether doses higher than the current recommended 300 mg monthly dosage of aerosolised pentamidine provide more efficacy before such an alternative prophylactic treatment is generally adopted for patients who cannot tolerate other systemic agents.

Acute gastroenteritis in infants under 6 months old

Sixty two babies under the age of 6 months who were admitted with gastroenteritis completed a study of gradual refeeding compared with abrupt refeeding after a period of rehydration. There was no difference in the incidence of recurrence of diarrhoea due to lactose intolerance, effect on weight, or duration of hospital stay. Twenty six babies (42%) had recurrence of diarrhoea after refeeding, all of whom settled with the introduction of a lactose free soya based formula. Well nourished babies under 6 months of age with mild to moderately severe gastroenteritis can be fed immediately with full strength milk feeds after rehydration. The introduction of a lactose free soya based preparation may provide an alternative to repeated attempts at regrading with cows' milk feeds in those patients with lactose intolerance.

Once-weekly fluconazole to prevent recurrence of oropharyngeal candidiasis in patients with AIDS and AIDS-related complex: a double-blind placebo-controlled study

Fluconazole 50 mg daily for 14-28 days was effective in the treatment of patients with AIDS and AIDS-related complex with severe oropharyngeal and oesophageal candidiasis. Of 24 patients entered, 17 (81%), including seven with oesophageal candidiasis, were clinically cured and two (9.5%) improved at the end of treatment. Following clinical cure, 14 patients were entered into the double-blind phase of the study, where fluconazole (150 mg) or placebo capsules were given once weekly. Treatment was double blind. Fluconazole 150 mg once weekly was found to be effective in maintaining patients both clinically and mycologically free of oropharyngeal candidiasis.

Successful late treatment of venous air embolism with hyperbaric oxygen

A case of haemodialysis-associated venous air embolism is described. The patient commenced hyperbaric oxygen therapy 21 hours after the event when, despite appearing decerebrate, he made a complete recovery. This case underlines the importance of all clinicians being aware of those centres with facilities for hyperbaric therapy and the need to refer all patients with cerebral air embolism even following a prolonged delay.

Does isolation of patients with infections induce mental illness?

Forty-one patients admitted into single-bedded isolation cubicles in an infectious diseases unit were assessed for evidence of mental disturbance. By use of the Crown-Crisp Experimental Index as a measure of mental state, the scores for somatic anxiety, free floating anxiety, and the total score were found to be significantly raised on admission, falling towards those found in a control general practice population by the time of discharge from hospital. Higher scores were associated with a past history of mental illness. There was, however, no statistical correlation between the psychological indices and consumption of alcohol, smoking, or patient's sex. Clinically apparent behavioural disturbance, mainly anxiety and agitation, was seen in 12 patients. Overall, patients expressed a preference for single rooms and did not find the isolation rituals disconcerting. The findings indicate that anxiety in patients with acute infections is more related to their illness and referral to hospital than to their imposed isolation. Only those patients with a past psychiatric history are likely to benefit from transfer to an open ward during convalescence.

A double-masked, placebo-controlled trial of acyclovir cream in immunocompetent patients with herpes zoster

Sixty-four patients with herpes zoster were entered into a randomised double-masked, placebo-controlled trial of 5% acyclovir cream applied five times daily for 5 days. Of these patients, 56 were included in the final analysis (26 acyclovir, 30 placebo). Significant and objective differences in either progression of the rash, severity of acute pain or incidence of post-herpetic neuralgia were not observed. Although significantly more rashes involuted in the acyclovir group, this isolated finding cannot be explained. Twenty-two patients (12 acyclovir, 10 placebo) experienced erythema or desquamation or both during treatment with the cream. The similar incidence of skin reactions in both groups suggests that they were related to the cream base rather than the acyclovir.

Infection of cardiac mural thrombus associated with left ventricular aneurysm

Infection is a rare complication of cardiac mural thrombus and may prove difficult to diagnose and treat. We describe a patient with infected thrombus associated with a left ventricular aneurysm, involving Salmonella typhimurium. Cross-sectional echocardiography proved helpful in establishing the diagnosis.

Toxoplasmosis associated with digital vasculitis and immunodeficiency--a dilemma in diagnosis

We present a case of acquired toxoplasmosis associated with severe digital vasculitis--a previously unreported finding. The rise in Toxoplasma gondii antibody titres may have been attenuated by impaired cellular immunity, and this poses a problem for diagnosis.

Micro-organisms in gastroenteritis

We present bacteriological and virological findings together with salient clinical features from a prospective study of 447 children aged under 2 years admitted to hospital with infectious gastroenteritis. Putative pathogenic micro-organisms were identified in the stools of 75% of these children. Eight identifiably distinct groups of viruses, found on electron microscopy and tissue culture were present in 67% of patients--rotavirus was detected most frequently. Pathogenic bacteria (salmonellas, shigellas, Escherichia coli, and Campylobacter jejuni--but excluding Clostridium difficile) were found in 16% only. Altogether 4 X 9% of 390 patients had gastroenteritis associated with Cl difficile toxin. The mean duration of diarrhoea was shortest in patients with identifiable virus, with rotavirus having a mean of 5 X 01 days, and was longest in patients with pathogenic bacteria in the stools (11 X 14 days). The finding of more than one type of virus did not seem to be associated with a significantly increased duration of diarrhoea. There are few clinical features which can be associated specifically with any particular micro-organism or groups of these. Multiple organism isolation was common, but the severity of the illness in those patients with at least two types of organism was not greater. Certain viruses, including the norwalk-like virus, known to be associated with outbreaks of gastroenteritis were found as frequently in a group of patients who did not have diarrhoea studied for comparison. Virus was still detectable in the stools of up to 40% of asymptomatic children on the day of discharge.

Double-blind placebo-controlled trial of erythromycin in the treatment of clinical campylobacter infection

In a double-blind placebo-controlled trial in patients hospitalized with campylobacter infection, erythromycin lessened pain and curtailed the carriage state but otherwise did not alter the natural course of the illness, which proved to be a short-lived, self-limiting one, even in this selected group of hospitalized patients; the majority had become asymptomatic by the time of the bacteriological diagnosis. The rarity of bacteraemia is highlighted by the study.

Clostridium difficile and its cytotoxin in infants admitted to hospital with infectious gastroenteritis

During a prospective study of infectious gastroenteritis in children under 2 years, 19 out of 390 patients (4.9%) were found to have Clostridium difficile cytotoxin in the faeces. In several there was no history of use of antibiotics. The symptoms of many infants with toxin settled spontaneously, but one child became acutely and severely ill and developed a toxic megacolon and five others required, and responded to, vancomycin. Cl difficile was cultured from the stools in 191 (49%) of the children. The highly significant increased prevalence of past use of antibiotics in 118 control patients was not associated with an increased incidence of either isolation of Cl difficile or presence of faecal cytotoxin. Cl difficile should not be overlooked as a cause of acute diarrhoea and vomiting in children under 2 years.

Contemporary gastroenteritis of infancy: clinical features and prehospital management

In a prospective survey carried out over 12 months 447 children aged under 2 years were admitted to the Manchester Regional Infectious Diseases Unit for treatment of gastroenteritis. Comparison of the children with those in a survey 15 years previously in the same unit showed that the illness was milder than in the earlier series, with no deaths and with lower incidences of hypernatraemia (1%), uraemia (8%), and dehydration (14%). These improved findings occurred despite several deficiencies of care in the prehospital phase of the illness, particularly poor compliance with the widely recommended guidelines for fluid and dietary management in infantile gastroenteritis.

How useful is cerebrospinal fluid lactate estimation in differential diagnosis of meningitis?

Cerebrospinal fluid lactate (CSF) was measured by a rapid enzymatic method in 230 patients admitted with a suspected diagnosis of central nervous system infection. In all untreated cases of bacterial meningitis the levels exceeded 4.3 mmol/l and fell below 3.9 mmol/l in most patients with virus meningitis. We believe values of 3.9-4.3 mmol/l should be considered borderline as occasional CSF samples in cases of virus meningitis yield values in this range. However, distinction between untreated pyogenic meningitis and virus meningitis is rarely problematic in clinical practice, so routine use of the test as an emergency procedure offers no extra advantage. The test is unlikely to be of much help in differentiating partly treated bacterial meningitis from virus meningitis, but it is a valuable additional procedure for differentiating tuberculous meningitis from virus meningitis, highly modified bacterial meningitis and parameningeal septic states.

Crohn's Disease with Fistulae Involving Joints

Two cases of Crohn's disease with unusual manifestations of fistulae involving joints are reported. One case with a fistula from the rectum through the pelvis presented with an abscess adjacent to the left hip joint. The second presented acutely with inflammation and swelling of the right thigh suggesting thrombophlebitis. This patient died from septicaemia and was found at postmortem to have ileal Crohn's disease with fistulae into the thigh, producing septic arthritis of the knee. The possibility of underlying Crohn's disease should be considered in patients who develop abscesses adjacent to the pelvis, or physical signs suggesting thrombophlebitis of the thigh.

Whooping cough--a study of severity in hospital cases

In an attempt to determine the clinical severity and prognosis of children admitted to hospital with whooping cough, 127 patients were studied prospectively during a 12-month period. Clinical and laboratory criteria were used and the impression gained was that most cases were mild, although 3 children were dangerously ill and at least 30% had symptoms lasting 2 months or longer. There were no deaths, and no permanent sequelae were noted. The mean age of patients was higher than in other series, which might have accounted for the fairly low severity. Although there was some evidence of a decline in severity and mortality, whooping cough is still an unpleasant and protracted illness.