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Emerging Infectious Diseases | 2008

Ehrlichia chaffeensis in Child, Venezuela

María del Carmen López Martínez; Clara Nancy Gutiérrez; Franklin Monger; Johanny Ruiz; Akemys Watts; Víctor Mijares; María G. Rojas; Francisco J. Triana-Alonso

To the Editor: Human monocytic ehrlichiosis is a tick-borne infectious disease caused by Ehrlichia chaffeensis (1). Serologic studies have indicated E. chaffeensis infection in Latin American countries: Venezuela (2), Mexico (3), Argentina (4), Chile (5), and Brazil (6). However, no molecular evidence for E. chaffeensis has been reported. In December 2001, a 9-year-old boy was admitted to a hospital in Carabobo, Venezuela, after 3 days of fever (39°C–41°C), malaise, anorexia, headache, abdominal pain, and cutaneous tick-bite lesions. During the 6 weeks before admission, the patient had been exposed to ticks in a rural area (Cojedes, Venezuela). At the time of physical examination, the patient appeared acutely ill with fever (41°C), dehydration, somnolence, conjunctivitis, facial edema, cervical adenomegaly, soft depressible abdomen painful to palpation, and hepatomegaly. Cardiopulmonary examination found regular cardiac sounds with systolic tricuspid murmur and abnormal bilateral respiratory sounds (rhonchi). Skin examination showed multiple tick bites and an erythematous maculopapular rash. Appropriate informed consent was obtained. Blood values were as follows: leukocytes 6,280 cells/mm3 (84% neutrophils, 13% lymphocytes, 2% monocytes, 1% eosinophils), platelets 130,000/μL, hemoglobin 12.5 g/dL, glucose 102 mg/dL, blood urea 28.3 mg/dL, creatinine 0.9 mg/dL, aspartate aminotransferase (AST) 20.4 U/L, alanine aminotransferase (ALT) 54.4 U/L, erythrocyte sedimentation rate (Katz index) 15 mm/h, prothrombin time ratio 1.02, partial thromboplastin time –2.8 s. Radiographs of the thorax showed bilateral infiltrate. Echocardiogram showed minor tricuspid insufficiency. Serologic tests were negative for Epstein-Barr and hepatitis B and positive for cytomegalovirus and hepatitis A viruses. Blood and stool cultures were negative. Blood samples were taken 4 and 35 days after illness onset; buffy-coat smears were stained with Dip Quick (Jorgensen Laboratories, Inc., Loveland, CO, USA), and immunologic and PCR tests were performed. Immunoglobulin (Ig) M against dengue virus was present at days 4 and 35 of illness; IgG against dengue was absent on day 4 and present on day 35. PCR and viral isolation tests for dengue virus were negative. Serologic tests for E. chaffeensis (indirect immunofluorescence) were also negative on day 4 and positive (256) on day 35. Detection of Ehrlichia species–specific DNA was performed by using nested PCR as described (7). Starting on the first day of hospitalization, the patient was treated with doxycycline (14 days) and chloramphenicol (8 days). After 24 hours, malaise, headache, facial edema, and conjunctivitis improved. After 48 hours, fever and rash were gone. After 3 days, his appetite improved; progressively over time, cervical adenomegaly and cutaneous lesions improved. Abdominal pain persisted for 7 days after treatment. Nausea and vomiting started 2 days after admittance; on day 7, vomit was of coffee-ground consistency. All remaining symptoms abated thereafter. The patient had diarrhea during days 3–6 after admittance; hepatomegaly disappeared after 4 days. Ultrasonographic images of the abdomen indicated acute cholecystitis and hepatosplenomegaly; endoscopic examination of the upper digestive tract showed hyperplasia, hyperemia, and linear and pseudomembranous lacerations in the middle and distal thirds of the esophagus (Mallory-Weiss syndrome) and moderate erythema of the stomach. Test results for Helicobacter pylori and Giardia lamblia were negative. Laboratory results showed leukopenia and monocytosis on day 5 of illness. Leukocyte count was within reference range thereafter; thrombocytopenia was present until day 7 (99,000/mm3). ALT was elevated from day 3 and peaked (481 IU) on day 7. AST levels increased on day 5 and peaked (215 IU) on day 7. Both values decreased progressively to reference levels (after 25 days for ALT and 46 days for AST). Lactic dehydrogenase was elevated for 9 days while erythrocyte count, sedimentation rate, and serum glucose, amylase, urea, creatinine, bilirubin, calcium, sodium, and potassium remained within reference limits. The patient was released after 8 days of hospitalization. The buffy-coat smear performed 4 days after illness onset showed basophilic intracytoplasmic inclusions inside vacuoles of lymphocytes and monocytes, with typical features of morulae reported for human monocytic ehrlichiosis (Figure). Nested PCR analysis was positive for E. chaffeensis, and sequencing of the amplified DNA fully confirmed the 16S rRNA targeted sequence. Figure Peripheral blood smears (buffy-coat preparation) showing variable-sized basophilic inclusions (arrows) in mononuclear cells from a 9-year-old boy with human monocytic ehrlichiosis, Carabobo, Venezuela. Dip Quick (Jorgensen Laboratories, Inc., Loveland, ... This report provides molecular evidence of E. chaffeensis infection in a patient with acute disease in Venezuela. A previous case of human monocytic ehrlichiosis in a 17-month-old girl in Venezuela has been demonstrated serologically (2). E. canis in an asymptomatic patient in Venezuela has been demonstrated by PCR and culture isolation (8) and was recently demonstrated in symptomatic patients (9). Excluding the esophageal lesions (Mallory-Weiss syndrome), our case is compatible with cases reported previously (10). The clinical manifestations of ehrlichiosis are similar to those of dengue fever and mononucleosis, both common diseases in Venezuela. The positive anti-dengue IgM and the seroconversion of the IgG together with the negative PCR and isolation results suggest a recent, inactive infection with dengue virus. According to our findings, ehrlichiosis should be a differential diagnosis for febrile patients who have thrombocytopenia, hepatomegaly, and recent exposure to ticks. Although Amblyomma americanum, the main known vector of E. chaffeensis, has not been reported in Venezuela, Rhipicephalus sanguineus and A. cajennense are abundant in rural areas of Venezuela; their ability to be vectors should be investigated.


Veterinary Clinical Pathology | 2008

Cultivation and molecular identification of Ehrlichia canis and Ehrlichia chaffeensis from a naturally co‐infected dog in Venezuela

Clara Nancy Gutiérrez; María del Carmen López Martínez; Erlinda Sánchez; Marisol De Vera; María G. Rojas; Joahnny Ruiz; Francisco J. Triana-Alonso

BACKGROUND Diagnosis of canine ehrlichiosis in Venezuela is normally performed by examination of buffy coat smears (BCS). Characteristic inclusion bodies are frequently observed in leukocytes and platelets from dogs with clinical signs of the disease. OBJECTIVE The purpose of this study was to investigate the co-infection of a dog with Ehrlichia canis and E hrlichia chaffeensis using microbiological and molecular techniques. METHODS Primary cultures of monocytes from a dog showing signs of ehrlichiosis were performed. Ehrlichial inclusions in blood cells were demonstrated by BCS and in cultured cell smears with direct immunofluorescence and Dip Quick staining. Nested PCR analysis was performed with DNA from blood samples and cultures, using primers specific for E. canis and E. chaffeensis. The amplified DNA fragments were sequenced to confirm the specificity of the amplifications. RESULTS The BCS of the naturally infected dog contained intracellular morulae. Ehrlichial inclusions were observed 9 days after inoculation of the primary cultures. After 3 passages with monocytes from a healthy dog, 65% of infected cells, and cells with >60 morulae were observed. A healthy female German Shepherd dog, seronegative for E. canis and E. chaffeensis antigens and without contact to ticks, was inoculated with an infected culture. The animal developed signs of canine monocytic ehrlichiosis and became seropositive. Nested PCR results and sequencing of amplified DNA fragments demonstrated the simultaneous presence of E. canis and E. chaffeensis in both dogs. CONCLUSIONS This is the first report of E. chaffeensis in dogs in South America. This organism was previously identified in dogs by PCR only in the United States.


Transactions of The Royal Society of Tropical Medicine and Hygiene | 2015

Seroprevalence and risk factors of toxocariasis in preschool children in Aragua state, Venezuela

María del Carmen López Martínez; Héctor García; Liliana Figuera; Verónica González; Félix Lamas; Katherinne López; Víctor Mijares; Yeasiry Corrales; María Lares; Elizabeth Ferrer

BACKGROUND Toxocariasis is a widespread zoonotic disease caused by the nematode Toxocara canis. In Venezuela, the magnitude of the disease is unknown and seroepidemiological studies have not been previously carried out in Aragua state. METHODS A cross-sectional field study was conducted in eight preschools in three municipalities from Aragua state in Venezuela. A total of 224 children aged between 1 and 6 years were studied (43.8% [98/224] male and 56.2% [126/224] female). Blood samples were obtained for detection of IgG antibodies against Toxocara spp. using ELISA. Participating families were given a questionnaire and children included in the study were clinically evaluated by paediatricians, and signs and symptoms observed were included in the questionnaires. RESULTS Anti-Toxocara spp. antibodies were detected in 29.0% (65/224) of children. The seroprevalence in the different preschools studied ranged between 4.2% and 60.6%. Leucocytosis and eosinophilia were also detected. Analysis of questionnaires indicated that boys were more at risk than girls. Younger children were also more at risk. Other significant risk factors were socio-economic strata (IV and V), inadequate improvised housing, earthen flooring indoors and outdoors and the presence of dogs in preschools. CONCLUSIONS The results from this work show the presence of infection and a high prevalence of antibodies against Toxocara spp. in the studied municipalities and indicate that toxocariasis poses a serious health problem to preschool children in Aragua state.


Transactions of The Royal Society of Tropical Medicine and Hygiene | 2018

Epidemiological, clinical and laboratory features of toxocariasis in school children from Aragua State, Venezuela

María del Carmen López Martínez; Jesica Montero; Adriana Pineda; Víctor Mijares; María Lares; Emily Catalano; Elizabeth Ferrer

Background Toxocariasis is a widespread zoonosis caused by canine and feline Toxocara spp. In Venezuela, seroepidemiological studies in Aragua State have been carried out only in preschool children. The objective of this study was to determine the prevalence of anti-Toxocara spp. antibodies and identify clinical symptoms and risk factors of Toxocara spp. infection in school children in two municipalities of Aragua State of Venezuela. Methods A cross-sectional field study with 259 children between 6 and 12 y of age was conducted in six schools in Aragua State. Immunoglobulin G antibodies against Toxocara spp. by enzyme-linked immunosorbent assay, haematology and eosinophil counts were detected in blood. Participating families filled in a questionnaire and studied children were clinically evaluated by paediatricians. Results Anti-Toxocara spp. antibodies were detected in 14.3% of children. The seroprevalence in the schools studied ranged from 4.4% to 24.1%. Statistical associations with eosinophilia, decreased visual acuity, eyestrain, headache and paleness were found. Significant risk factors were contact with dogs, playing with dogs and playing with soil. Conclusions The identification of risk factors and their association with infection suggest that the infection is a problem in the municipalities studied, so screening for toxocariasis in school children should be recommended.


Alimentaria | 2003

La biotecnología y sus aplicaciones al sector agroalimentario

María Adela Rodríguez López; Rosa María Blanca Herrera; María del Carmen López Martínez


Revista de la Sociedad Venezolana de Microbiología | 2010

Frecuencia de antiestreptolisina O y antidesoxirribonucleasa B como indicador de infección estreptocócica en estudiantes de una unidad educativa del estado Aragua

Clara Nancy Gutiérrez; María Chacón; María del Carmen López Martínez; Bethelgeuse Sibrian; Yaraceli Márquez; Edmundo Herrera; Liliana Torres; Luis Pérez-Ybarra


Investigacion Clinica | 1999

Ultrastructural identification of Ehrlichia sp in an experimentally infected dog in Venezuela

Gutiérrez N; María del Carmen López Martínez; Cruz Arraga-Alvarado; Antonio Bretaña; Italo Pacheco; Guillermo Comach


Alimentación, equipos y tecnología | 1997

Estudio sobre la vida comercial o útil de la trucha fresca eviscerada y filetes ("Oncorhynchus mykis")

M. de Valdivia Garvayo; Reyes Artacho Martín-Lagos; Purificación Muros Guadix; María Dolores Ruiz López; María del Carmen López Martínez


Alimentaria | 2001

Elementos tóxicos en alimentos, bebidas y envases

María Adela Rodríguez López; Carmen Cabrera Vique; María del Carmen López Martínez; Miguel Navarro Alarcón


Alimentaria | 2000

Study of the influence of the ageing system on the main physicochemical parameters in commercial brandies

J. Quesada Granados; Rafael Giménez Martínez; Herminia López García de la Serrana; Marina Villalón Mir; María del Carmen López Martínez

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Lucio López Martínez

Autonomous University of Zacatecas

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