Pulmonary hemorrhage in an infant following 2 weeks of fungal exposure

BACKGROUND: Exposure to indoor fungus growth and tobacco smoke has been epidemiologically linked to unexplained pulmonary hemorrhage in infants. OBJECTIVE: To describe the 40-day-old male infant who had been exposed to fungi for a discrete 2-week period followed by acute exposure to environmental tobacco smoke prior to development of a life-threatening pulmonary hemorrhage. PATIENT AND METHODS: History and clinical evaluation of the infant immediately followed the pulmonary hemorrhage. Air and surface sampling for isolation and identification of fungal growth in the dwelling where the infant resided before the acute hemorrhage was accomplished when the homeowner returned from vacation 4 months after the clinical event. RESULTS: Two fungi associated with mycotoxin production were cultured from surface samples collected in the residence: Penicillium (possibly Penicillium purpurogenum) and a Trichoderma species. Stachybotrys atra was not isolated from air or surface samples. Environmental tobacco smoke exposure occurred over a discrete several-hour period prior to onset of the acute pulmonary hemorrhage. CONCLUSIONS: Avoidance of unnecessary exposure of infants to fungus growth in water-damaged environments or exposure to tobacco smoke is prudent. Further investigation into the toxic effects of indoor fungi as causes of infantile pulmonary hemorrhage is warranted.     

HIV dynamics with multiple infections of target cells

The high incidence of multiple infections of cells by HIV sets the stage for rapid HIV evolution by means of recombination. Yet how HIV dynamics proceeds with multiple infections remains poorly understood. Here, we present a mathematical model that describes the dynamics of viral, target cell, and multiply infected cell subpopulations during HIV infection. Model calculations reproduce several experimental observations and provide key insights into the influence of multiple infections on HIV dynamics. We find that the experimentally observed scaling law, that the number of cells coinfected with two distinctly labeled viruses is proportional to the square of the total number of infected cells, can be generalized so that the number of triply infected cells is proportional to the cube of the number of infected cells, etc. Despite the expectation from Poisson statistics, we find that this scaling relationship only holds under certain conditions, which we predict. We also find that multiple infections do not influence viral dynamics when the rate of viral production from infected cells is independent of the number of times the cells are infected, a regime expected when viral production is limited by cellular rather than viral factors. This result may explain why extant models, which ignore multiple infections, successfully describe viral dynamics in HIV patients. Inhibiting CD4 down-modulation increases the average number of infections per cell. Consequently, altering CD4 down-modulation may allow for an experimental determination of whether viral or cellular factors limit viral production.     

Transient hypothyroidism in a breastfed infant after maternal use of iodoform gauze

We describe transient hypothyroidism induced in a 2 week-old breastfed infant by maternal use of iodoform gauze for a perirectal abscess. The initial newborn thyroid screen was normal. Low levels of thyroid hormone were discovered during a routine second newborn screen. Thyroid function has since normalized with short-term therapy with thyroxine and after the mother discontinued use of the packing iodoform gauze. This case illustrates the need to avoid iodine-containing products in breastfeeding mothers.     

Intravenous cyclophosphamide-resistant systemic lupus erythematosus in Arizona

Systemic lupus erythematosus (SLE) tends to be severe and to have a variable response in childhood. We undertook this retrospective study to assess response rates and outcome in 14 children with SLE. Mean age at onset was 12.8±3.1 years. Ten patients were female and 4 were male, and 12 patients (86%) were Hispanic. Creatinine clearance prior to therapy was 104±36 ml/min. All had hematuria and proteinuria with a protein/creatinine ratio of 3.9±4.8. WHO classification of renal biopsies revealed class IV in 64%, class III in 21%, and class V in 14%. Patients were treated with 6-monthly pulses of intravenous cyclophosphamide (IVCY) followed by longer-duration pulses. The mean duration of follow-up was 3.7±3.3 years. Of the 14 patients, 3 (21%) achieved systemic remission but all relapsed subsequently; 7 of 14 achieved renal remission, although 6 relapsed. Six (42%) had adverse outcomes, defined by death, dialysis, or need for bone marrow transplant. All 6 had failed 6 months of IVCY, suggesting that patients who demonstrate resistance to initial IVCY therapy have an unfavorable outcome and a high likelihood of complications. In summary, we report a poor response to standard therapeutic protocols with higher relapse rates, as well as significant adverse outcomes.     

Sickle beta-thalassemia presenting as orbital compression syndrome

Orbital compression syndrome is caused by disorders of varying etiologies involving the orbit and presents with ocular and extraocular dysfunction. Ocular involvement of sickle cell disease is uncommon. A 17-year-old male presented with low backache and proptosis of both eyes of 5 days duration without past history of pain crisis or transfusion. Examination revealed pallor, icterus, bilateral proptosis, conjuctival chemosis, and symmetrical restriction of ocular movements with preserved visual acuity. He was drowsy with no other focal deficits. The fundus showed macular edema, venous engorgement, and no hemorrhage. His peripheral smear showed presence of sickle cells. Computed tomography (CT) scan of the orbit revealed orbital subperiosteal hematomas. CT head images showed epidural hematoma in the frontal lobe. High-performance liquid chromatography (HPLC) and mutation studies revealed sickle beta-thalassemia in the patient. He was managed with supportive care, transfusions to keep hemoglobin above 10 g/dl, and hydroxyurea. The patient recovered fully and remained well during follow-up of 12 months. Our case was unique for presenting as orbital compression syndrome without any history of vaso-occlusive crisis.     

Hyponatremic hypertensive syndrome (HHS) in an 18-month old-child presenting as malignant hypertension: a case report

Background  

The combination of hyponatremia and renovascular hypertension is called hyponatremic hypertensive syndrome (HHS). Malignant hypertension as a presentation has been reported in adults with HHS but is rare in children.     

Meta-analysis: Effect of hepatitis C virus infection on mortality in dialysis

BACKGROUND: The natural history of hepatitis C virus infection among patients on long-term dialysis treatment remains incompletely understood. Efforts to elucidate the natural history of hepatitis C virus in this population are difficult because of the slowly progressive nature of hepatitis C virus with often an unrecognized onset in patients whose life-expectancy is substantially diminished by end-stage renal disease. AIM: To conduct a systematic review of the published medical literature concerning the impact of hepatitis C virus infection on the survival of patients receiving chronic dialysis. The relative risk of mortality was regarded as the most reliable outcome end-point. METHODS: We used the random effects model of DerSimonian and Laird to generate a summary estimate of the relative risk for mortality with hepatitis C virus across the published studies. RESULTS: We identified four clinical trials (2341 unique patients); three (75%) of them were prospective, cohort studies; the fourth was a case-control study. Pooling of study results demonstrated that presence of antihepatitis C virus antibody was an independent and significant risk factor for death in patients on maintenance dialysis. The summary estimate for relative risk was 1.57 with a 95% confidence interval (CI) of 1.33-1.86. A test for homogeneity of the relative risks across the four studies gave a P-value of 0.77. As a cause of death, hepatocellular carcinoma and liver cirrhosis were significantly more frequent among antihepatitis C virus-positive than -negative dialysis patients. CONCLUSIONS: This meta-analysis demonstrates that antihepatitis C virus-positive patients on dialysis have an increased risk of mortality compared with hepatitis C virus-negative patients. The excess risk of death in hepatitis C virus-positive patients may be at least partially attributed to chronic liver disease with its attendant complications. Clinical trials with extended follow-up are currently under way to assess the effect of hepatitis C virus treatment on the excess risk of mortality in this population.