Fatal respiratory tract diphtheria apparently caused by nontoxigenic strains ofCorynebacterium diphtheriae

Abstract

A major diphtheria epidemic affecting the whole population of St. Petersburg started in 1990. During the period of 1991 to 1995, 4600 patients with clinical respiratory tract diphtheria were treated in Botkin's Hospital. From 112 (2.4%) of these patients only a nontoxigenic strain of Corynebacterium diphtheriae was isolated. Three patients with this strain who were suffering from clinical disease consistent with classical toxic diphtheria died. All had myocarditis, two had asphyxia due to membrane formation in the lower respiratory tract, and one had severe polyneuritis. In two patients the causative agent was of the biotype mitis and in the third intermedius, whereas the prevailing epidemic strain was of the biotype gravis. As the clinical presentation of the disease in the three patients who died was typical of toxic diphtheria, it is considered likely that the immunodiffusion test for toxin production in vitro may fail to detect strains of Corynebacterium diphtheriae producing toxin in vivo.

Fibrinogen binds to nontoxigenic and toxigenic Corynebacterium diphtheriae strains

“…Differences in the abilities to bind to and to convert Fbn to fibrin may partially explain differences in the extent of pseudomembrane formation by C. diphtheriae strains, including cases of catarrhal diphtheria. Therefore, the data of the present study may also help to explain why nontoxigenic strains may cause pharyngitis (Jephcott et al 1975, Wilson 1995, Rakhmanova et al 1997, Bonnet & Begg 1999.…”

“…However, the association of nontoxigenic strains with localized disease and with cases of invasive infection has become recognized, particularly with endocarditis (Gubler et al 1998, Galazka 2000, Mattos-Guaraldi et al 2000, Kanungo et al 2002, Gomes et al 2009). Various authors share the opinion that nontoxigenic strains may be responsible for pharyngitis and should be treated (Jephcott et al 1975, Wilson 1995, Rakhmanova et al 1997, Bonnet & Begg 1999. However, it is also emphasized that additional studies are still required to obtain more complete information on the pathogenicity or copathogenicity of nontoxigenic C. diphtheriae associated with cases of infection in the respiratory tract (Reacher et al 2000, Gomes et al 2009.…”

A Case of Necrotizing Epiglottitis Due to NontoxigenicCorynebacterium diphtheriae

“…21 Commonly reported subtypes of nontoxigenic disease include gravis and belfanti, the latter of which may have a selective advantage by tropism for the respiratory tract and the subtype seen in our patient. 2,20 The reported cases from Western Europe and Japan all isolated biotype mitis. 18,19 There have been no reports of C diphtheriae causing necrotizing epiglottitis, a syndrome that clinically overlaps with diphtheria.…”

“…1 Worldwide, toxigenic diphtheria remains endemic in countries with low vaccination coverage, including 7088 cases reported in 2008. 1,2 In the early 1990s, 157 000 cases and .5000 reported deaths occurred in the Soviet Union. 1,2 As recent as 2013, an outbreak occurred in a resettlement camp in Kandahar, Afghanistan, resulting in 50 cases and 3 deaths [1][2][3] Seventy-four percent of the cases in Afghanistan were in children ages 5 to 14.…”

“…1,2 In the early 1990s, 157 000 cases and .5000 reported deaths occurred in the Soviet Union. 1,2 As recent as 2013, an outbreak occurred in a resettlement camp in Kandahar, Afghanistan, resulting in 50 cases and 3 deaths [1][2][3] Seventy-four percent of the cases in Afghanistan were in children ages 5 to 14. 3 Severe disease is most often seen with toxigenic diphtheria but can be seen with the non-toxin-producing form, especially in immunocompromised patients or those with predisposing conditions, such as intravenous drug users and homeless people.…”