Antimicrobial resistance of Mycobacterium tuberculosis isolates from children in Greece, 1994-2004.

OBJECTIVE: To document the prevalence of resistance to various agents of Mycobacterium tuberculosis strains derived from children over 1994-2004. DESIGN: We prospectively studied the susceptibility patterns of 77 strains of M. tuberculosis isolated from the same number of children, which provided 112 positive samples. RESULTS: Most children were boys (53.2%), native Greeks (87%) and aged under 2 years (41.5%). Sample origin was mainly gastric fluid (97 cases, 86.6%). Sixty-one isolates (79.2%) were susceptible to all anti-tuberculosis agents and 16 (20.8%) were resistant to > or =1 drug. Multidrug resistance (MDR), resistance to at least isoniazid (INH) and rifampicin (RMP), was seen in three cases (3.9%). On comparing resistance to INH, RMP and streptomycin (SM) and MDR in children and adults diagnosed with tuberculosis in our centre during the same time period, SM resistance was significantly more common in children (P < 0.001), while a trend for increased resistance to INH was also observed in children (P = 0.079). CONCLUSION: Resistance of M. tuberculosis isolates to the first line anti-tuberculosis drugs appears to be comparable in children and adults in Greece, while SM resistance appears to be more common in children. Tracing the sources of these children is important for the effective surveillance and treatment of tuberculosis.     

Agnogenic myeloid metaplasia with pulmonary hematopoiesis

Agnogenic myeloid metaplasia (AMM) is characterized by bone marrow fibrosis, splenomegaly and leukoerythroblastic anemia and is frequently accompanied by extramedullary hematopoiesis (EMH). Pulmonary interstitial EMH associated with myelofibrosis has rarely been described in the medical literature and is usually fatal. We report the case of a 77-year-old man with agnogenic myeloid metaplasia (AMM) treated with hydroxyurea, who seven years after diagnosis presented with dyspnea and severe hypoxemia. Radionuclide bone marrow scanning demonstrated increased tracer activity on the bases of both lungs, consistent with non-hepatosplenic EMH. Pulmonary EMH is rare in patients with AMM, but should be considered in patients with hypoxemia and respiratory distress.     

Clinical presentation of zygomycosis

Zygomycetes are filamentous fungi with a worldwide distribution. This class of fungi encompasses two orders, i.e. the Mucorales and the Entomophthorales. Members of the latter are associated with chronic cutaneous and subcutaneous infections that are limited to the tropics and rarely disseminate to internal organs. The order Mucorales includes several species involved in rhinocerebral, pulmonary, cutaneous, gastrointestinal and other less frequent infections in immunocompetent and immunocompromised individuals, and is characterized by a tendency to disseminate. Portals of entry of zygomycetes are usually the lungs, skin, and gastrointestinal tract. A characteristic property of zygomycetes is their tendency to invade blood vessels and to cause thrombosis—processes that result in subsequent necrosis of involved tissues. Risk factors associated with zygomycosis include prolonged neutropenia and use of corticosteroids, solid organ or haematopoietic stem cell transplantation, AIDS, poorly controlled diabetes mellitus, iron chelation with deferoxamine, burns, wounds, malnutrition, extremes of age, and intravenous drug abuse. Recently, the widespread use of voriconazole for prophylaxis or treatment of aspergillosis in patients with haematological malignancies has been linked with a rise in the numbers of cases of invasive zygomycosis. As the symptoms, clinical signs and imaging findings of these infections are non-specific, a high index of suspicion is required for timely diagnosis. Early diagnosis, correction of the underlying predisposing factors, aggressive surgical debridement of all infected tissues and lengthy administration of antifungals are the only potentially curative options for this rare but emerging invasive fungal infection.     

Orofacial viral infections in the immunocompromised host

Orofacial viral infections are common in immunocompromised patients. Herpes simplex virus (HSV) infections are the most common. Varicella-Zoster virus (VZV) infections are less common, but usually more severe. Epstein-Barr virus (EBV) may produce ulcers, lymphoproliferative syndromes or oral hairy leukoplakia (HL). Human herpes virus 6 (HHV 6) may be the etiology of recurrent aphthous stomatitis, while human herpes virus 7 (HHV 7) has an unclear role. Human herpes virus 8 (HHV 8) is the etiologic agent of Kaposi sarcoma. Human papilloma viruses (HPVs) cause warts, papillomas and epithelial hyperplasia. Molluscum contagiosum is caused by a poxvirus. All herpes viruses (HSV, VZV, CMV, EBV, HHV 6, HHV 7, HHV 8) and many HPVs are associated with neoplasias. Research is ongoing to clarify the role of other viruses in the development of infections and lesions in the orofacial area.     

Remission of a Chiasmatic Glioma in a Non-NF1 Patient After Brief Chemotherapy with Vincristine and Carboplatin: Case Report and Literature Review

We describe the case of an 8-year-old girl without neurofibromatosis, who presented with total loss of vision on the left eye, due to a chiasmatic mass with imaging characteristics of glioma, accompanied by a second asymptomatic mass in the middle cranial fossa, along the intracranial route of the right trigeminal nerve. The patient received a total of 10 weekly injections of vincristine and four injections of carboplatin every 3 weeks and achieved a very good partial response (97% volume reduction) after the nineth week of therapy with acceptable toxicity. Given the natural history of opticochiasmatic gliomas, we cannot rule out the possibility of a spontaneous regression. However, we believe the quick response accompanied by visual improvement was most likely due to chemotherapy. A trial of vincristine and carboplatin may be worthwhile in children with symptomatic chiasmatic gliomas, irrespective of their age.     

New antileukemic agents

Despite the tremendous progress in the treatment of childhood leukemias over the last 50 years, certain subgroups of children continue to have poor prognosis. Hence, there is a need for development of new antileukemic agents. In this review, the authors describe results of clinical trials of several new antileukemic compounds with different mechanisms of action (signal transduction inhibitors, nucleoside analogs, DNA hypomethylators, angiogenesis inhibitors, and monoclonal antibodies). Although most of these compounds are not used in pediatric leukemias, the concepts surrounding their clinical development are important to all pediatric hematologists/oncologists.     

Capnocytophaga gingivalis bacteremia detected only on quantitative blood cultures in a child with leukemia

Capnocytophaga species are inhabitants of the normal mouth flora. We describe the case of a 6-year-old-girl with leukemia and poor oral hygiene who developed bacteremia caused by Capnocytophaga gingivalis. The organism was detected only on quantitative blood cultures.     

Acute renal failure due to obstruction in Burkitt lymphoma

 Acute renal failure in Burkitt lymphoma is commonly the result of tumor lysis syndrome. We present a 15-year-old boy who developed hypertension, seizures, and acute renal failure due to extrinsic compression of the bladder and ureters by a large retrovesical Burkitt lymphoma. The causes of acute renal failure in Burkitt lymphoma and the incidence of acute urinary obstruction in this disease are reviewed. Received: 18 May 1998 / Revised: 30 June 1998 / Accepted: 1 July 1998